<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e65ee-c09f-7031-ad5b-bd5eabf78ffd,g:60a4eebe-2200-44c9-a068-bc667371505a-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://gpgi.com/role/CoverPage" xlink:type="simple" xlink:href="gpgi-20260630.xsd#CoverPage"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/CoverPage" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentInformationTable_019e65ee-c15a-75a3-92ed-1fc735a9a4cf" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentInformationTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentInformationTable_019e65ee-c15a-75a3-92ed-1fc735a9a4cf" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityListingsExchangeAxis_019e65ee-c15a-7aed-a225-7ba53e920711" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityListingsExchangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_dei_DocumentInformationTable_019e65ee-c15a-75a3-92ed-1fc735a9a4cf" xlink:to="loc_dei_EntityListingsExchangeAxis_019e65ee-c15a-7aed-a225-7ba53e920711" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_019e65ee-c15a-7aed-a225-7ba53e920711_default" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_EntityListingsExchangeAxis_019e65ee-c15a-7aed-a225-7ba53e920711" xlink:to="loc_dei_ExchangeDomain_019e65ee-c15a-7aed-a225-7ba53e920711_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_ExchangeDomain_019e65ee-c15a-70be-ab5b-efe3c9947e96" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ExchangeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_EntityListingsExchangeAxis_019e65ee-c15a-7aed-a225-7ba53e920711" xlink:to="loc_dei_ExchangeDomain_019e65ee-c15a-70be-ab5b-efe3c9947e96" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_exch_XNYS_019e65ee-c15a-7bcd-9678-2535b67b41b4" xlink:href="https://xbrl.sec.gov/exch/2026/exch-2026.xsd#exch_XNYS"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_ExchangeDomain_019e65ee-c15a-70be-ab5b-efe3c9947e96" xlink:to="loc_exch_XNYS_019e65ee-c15a-7bcd-9678-2535b67b41b4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019e65ee-c15a-75e6-b0fe-a0f096560c77" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentType_019e65ee-c15a-75e6-b0fe-a0f096560c77" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentQuarterlyReport_019e65ee-c15a-7417-8746-48b04a8de51f" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentQuarterlyReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentQuarterlyReport_019e65ee-c15a-7417-8746-48b04a8de51f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019e65ee-c15a-78eb-83c9-8c0e00d99dc5" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentPeriodEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentPeriodEndDate_019e65ee-c15a-78eb-83c9-8c0e00d99dc5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentTransitionReport_019e65ee-c15a-7fec-8543-9927271a0f15" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentTransitionReport"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentTransitionReport_019e65ee-c15a-7fec-8543-9927271a0f15" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019e65ee-c15a-7f28-b21c-df131495acf1" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFileNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityFileNumber_019e65ee-c15a-7f28-b21c-df131495acf1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019e65ee-c15a-7118-a1c6-0bf11db88c22" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityRegistrantName_019e65ee-c15a-7118-a1c6-0bf11db88c22" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019e65ee-c15a-72ca-8dca-1eb06fb33037" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019e65ee-c15a-72ca-8dca-1eb06fb33037" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019e65ee-c15a-7fae-83c4-713971d62a42" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityTaxIdentificationNumber_019e65ee-c15a-7fae-83c4-713971d62a42" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019e65ee-c15a-7b24-b3fb-ae7df44d2d8d" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityAddressAddressLine1_019e65ee-c15a-7b24-b3fb-ae7df44d2d8d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019e65ee-c15a-792d-b101-97c2dd20c03e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCityOrTown"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityAddressCityOrTown_019e65ee-c15a-792d-b101-97c2dd20c03e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019e65ee-c15a-7449-9dfa-b4ad59609a06" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressStateOrProvince"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityAddressStateOrProvince_019e65ee-c15a-7449-9dfa-b4ad59609a06" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019e65ee-c15a-7ce7-914e-3a340883ffb4" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityAddressPostalZipCode_019e65ee-c15a-7ce7-914e-3a340883ffb4" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019e65ee-c15a-7d46-9853-467d41e8db71" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CityAreaCode"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_CityAreaCode_019e65ee-c15a-7d46-9853-467d41e8db71" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019e65ee-c15a-7390-afb7-a906ef363bf7" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_LocalPhoneNumber_019e65ee-c15a-7390-afb7-a906ef363bf7" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019e65ee-c15a-7fc8-b8d9-70ab54be9302" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_Security12bTitle"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_Security12bTitle_019e65ee-c15a-7fc8-b8d9-70ab54be9302" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019e65ee-c15a-7e50-bb61-0ad9f7fa4d96" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_TradingSymbol"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_TradingSymbol_019e65ee-c15a-7e50-bb61-0ad9f7fa4d96" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019e65ee-c15a-7bdd-b857-7214931fb097" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_SecurityExchangeName"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_SecurityExchangeName_019e65ee-c15a-7bdd-b857-7214931fb097" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCurrentReportingStatus_019e65ee-c15a-73a9-b014-1103122cbb2e" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCurrentReportingStatus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityCurrentReportingStatus_019e65ee-c15a-73a9-b014-1103122cbb2e" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityInteractiveDataCurrent_019e65ee-c15a-76d4-b468-e37623774aad" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityInteractiveDataCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityInteractiveDataCurrent_019e65ee-c15a-76d4-b468-e37623774aad" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFilerCategory_019e65ee-c15a-7227-9518-564768dc14e8" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFilerCategory"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityFilerCategory_019e65ee-c15a-7227-9518-564768dc14e8" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntitySmallBusiness_019e65ee-c15a-71c6-9a61-7ed45724f0db" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntitySmallBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntitySmallBusiness_019e65ee-c15a-71c6-9a61-7ed45724f0db" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019e65ee-c15a-7f4a-9789-53d9149f9e63" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityEmergingGrowthCompany_019e65ee-c15a-7f4a-9789-53d9149f9e63" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityShellCompany_019e65ee-c15a-7655-b54e-1b1763638912" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityShellCompany"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityShellCompany_019e65ee-c15a-7655-b54e-1b1763638912" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_019e65ee-c15a-7816-a6ef-7d406151f614" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityCommonStockSharesOutstanding_019e65ee-c15a-7816-a6ef-7d406151f614" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019e65ee-c15a-7e0a-b40e-3e36126af276" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_EntityCentralIndexKey_019e65ee-c15a-7e0a-b40e-3e36126af276" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CurrentFiscalYearEndDate_019e65ee-c15a-7456-a5d1-6de4a109c634" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CurrentFiscalYearEndDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_CurrentFiscalYearEndDate_019e65ee-c15a-7456-a5d1-6de4a109c634" xlink:type="arc" order="25"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalYearFocus_019e65ee-c15a-7e74-8ef2-33f6490b13a7" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentFiscalYearFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentFiscalYearFocus_019e65ee-c15a-7e74-8ef2-33f6490b13a7" xlink:type="arc" order="26"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentFiscalPeriodFocus_019e65ee-c15a-786d-9ec2-bf9020509cee" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentFiscalPeriodFocus"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_DocumentFiscalPeriodFocus_019e65ee-c15a-786d-9ec2-bf9020509cee" xlink:type="arc" order="27"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019e65ee-c15a-72d0-a127-2e6c79e88bde" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_DocumentInformationLineItems_019e65ee-c15a-778f-b382-bcfd92322a4d" xlink:to="loc_dei_AmendmentFlag_019e65ee-c15a-72d0-a127-2e6c79e88bde" xlink:type="arc" order="28"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/CondensedConsolidatedBalanceSheets" xlink:type="simple" xlink:href="gpgi-20260630.xsd#CondensedConsolidatedBalanceSheets"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e65ee-c15a-744c-8ada-d263b11b5b0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e65ee-c15a-78cd-b1ad-d52f717cefa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-744c-8ada-d263b11b5b0b" xlink:to="loc_us-gaap_StatementTable_019e65ee-c15a-78cd-b1ad-d52f717cefa5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-7016-b759-d023c2f87879" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e65ee-c15a-78cd-b1ad-d52f717cefa5" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-7016-b759-d023c2f87879" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-7016-b759-d023c2f87879_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-7016-b759-d023c2f87879" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-7016-b759-d023c2f87879_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-73cc-9f43-9e727ab6ed87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-7016-b759-d023c2f87879" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-73cc-9f43-9e727ab6ed87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019e65ee-c15a-70ab-8baf-7a8fd3be4044" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-73cc-9f43-9e727ab6ed87" xlink:to="loc_us-gaap_CommonClassAMember_019e65ee-c15a-70ab-8baf-7a8fd3be4044" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-744c-8ada-d263b11b5b0b" xlink:to="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:to="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e65ee-c15a-7ae1-9b33-318839be9ea7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e65ee-c15a-7ae1-9b33-318839be9ea7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019e65ee-c15a-7f60-a6c0-88d0ed2a6ea2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_019e65ee-c15a-7f60-a6c0-88d0ed2a6ea2" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxReceivable_019e65ee-c15a-7f39-8caf-fefb0d8561a9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReceivable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:to="loc_us-gaap_IncomeTaxReceivable_019e65ee-c15a-7f39-8caf-fefb0d8561a9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_019e65ee-c15a-71f7-99cb-8de348dbdc7e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_019e65ee-c15a-733f-9c2e-1b7d5f91d296" xlink:to="loc_us-gaap_AssetsCurrent_019e65ee-c15a-71f7-99cb-8de348dbdc7e" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxAssetsNet_019e65ee-c15a-7903-a12e-1fb082e1266d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:to="loc_us-gaap_DeferredIncomeTaxAssetsNet_019e65ee-c15a-7903-a12e-1fb082e1266d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-721f-ba2c-a8caedf2c3d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:to="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-721f-ba2c-a8caedf2c3d4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e65ee-c15a-7cf3-9005-d5683b161f1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_019e65ee-c15a-7377-9951-dd396a8d6721" xlink:to="loc_us-gaap_Assets_019e65ee-c15a-7cf3-9005-d5683b161f1f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-744c-8ada-d263b11b5b0b" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:to="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_019e65ee-c15a-7cb5-92f1-f8a12cdb1d97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:to="loc_us-gaap_AccountsPayableCurrent_019e65ee-c15a-7cb5-92f1-f8a12cdb1d97" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_019e65ee-c15a-72d0-a631-90bad825fbf4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_019e65ee-c15a-72d0-a631-90bad825fbf4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_TaxReceivableAgreementLiabilityCurrent_019e65ee-c15a-7d43-a527-0722fbd4810c" xlink:href="gpgi-20260630.xsd#gpgi_TaxReceivableAgreementLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:to="loc_gpgi_TaxReceivableAgreementLiabilityCurrent_019e65ee-c15a-7d43-a527-0722fbd4810c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_019e65ee-c15a-7ad7-bc9b-a451302fddaf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_019e65ee-c15a-7f94-a608-67e8532e6f0a" xlink:to="loc_us-gaap_LiabilitiesCurrent_019e65ee-c15a-7ad7-bc9b-a451302fddaf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_TaxReceivableAgreementLiabilityNoncurrent_019e65ee-c15a-787e-ba21-28f0df64af24" xlink:href="gpgi-20260630.xsd#gpgi_TaxReceivableAgreementLiabilityNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:to="loc_gpgi_TaxReceivableAgreementLiabilityNoncurrent_019e65ee-c15a-787e-ba21-28f0df64af24" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e65ee-c15a-7917-93a3-e336272b0b5e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:to="loc_us-gaap_Liabilities_019e65ee-c15a-7917-93a3-e336272b0b5e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:to="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValue_019e65ee-c15a-7139-9b2b-4e2b35f68e20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_PreferredStockValue_019e65ee-c15a-7139-9b2b-4e2b35f68e20" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_019e65ee-c15a-7547-be74-444a07ef35da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_CommonStockValue_019e65ee-c15a-7547-be74-444a07ef35da" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValue_019e65ee-c15a-73b3-be25-95d376eace10" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_TreasuryStockValue_019e65ee-c15a-73b3-be25-95d376eace10" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapital_019e65ee-c15a-7809-a614-4ed77960f2f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_AdditionalPaidInCapital_019e65ee-c15a-7809-a614-4ed77960f2f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019e65ee-c15a-7ed3-9fab-c4513cefe0bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_019e65ee-c15a-7ed3-9fab-c4513cefe0bd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019e65ee-c15a-78d4-b862-c4a34a59eccd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_019e65ee-c15a-78d4-b862-c4a34a59eccd" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e65ee-c15a-7010-882c-fdbc6c448f19" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StockholdersEquityAbstract_019e65ee-c15a-7b3b-88c9-6a527eb48710" xlink:to="loc_us-gaap_StockholdersEquity_019e65ee-c15a-7010-882c-fdbc6c448f19" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e65ee-c15a-7063-ab5d-3757232df221" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_019e65ee-c15a-7c0d-b0c0-a3731172f1ff" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_019e65ee-c15a-7063-ab5d-3757232df221" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" xlink:href="gpgi-20260630.xsd#CondensedConsolidatedBalanceSheetsParenthetical"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e65ee-c15a-7dba-8782-cf9eadf725a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_StatementTable_019e65ee-c15a-7dba-8782-cf9eadf725a8" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-744b-af74-a3d87d03b0ac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e65ee-c15a-7dba-8782-cf9eadf725a8" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-744b-af74-a3d87d03b0ac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-744b-af74-a3d87d03b0ac_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-744b-af74-a3d87d03b0ac" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-744b-af74-a3d87d03b0ac_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-701d-9bad-78c7b94a2228" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-744b-af74-a3d87d03b0ac" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-701d-9bad-78c7b94a2228" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019e65ee-c15a-7950-b370-a2eb1c4ececb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-701d-9bad-78c7b94a2228" xlink:to="loc_us-gaap_CommonClassAMember_019e65ee-c15a-7950-b370-a2eb1c4ececb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_019e65ee-c15a-7135-8f4e-ffa052fecf46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_PreferredStockParOrStatedValuePerShare_019e65ee-c15a-7135-8f4e-ffa052fecf46" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_019e65ee-c15a-79b2-bef7-a87a8f2cd74f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_019e65ee-c15a-79b2-bef7-a87a8f2cd74f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesIssued_019e65ee-c15a-78c5-9d4d-3067bd8c0086" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_PreferredStockSharesIssued_019e65ee-c15a-78c5-9d4d-3067bd8c0086" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_019e65ee-c15a-75c1-a158-1f9475829c18" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_PreferredStockSharesOutstanding_019e65ee-c15a-75c1-a158-1f9475829c18" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019e65ee-c15a-7006-80d1-de8952d4d69b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019e65ee-c15a-7006-80d1-de8952d4d69b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019e65ee-c15a-7e59-89b7-32cc4b1f9e6d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019e65ee-c15a-7e59-89b7-32cc4b1f9e6d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesIssued_019e65ee-c15a-76d0-9374-2f9c324cc236" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_CommonStockSharesIssued_019e65ee-c15a-76d0-9374-2f9c324cc236" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019e65ee-c15a-7e82-9bc9-edd16fcf72a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-765d-9282-785b7c75729f" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019e65ee-c15a-7e82-9bc9-edd16fcf72a8" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/CondensedConsolidatedStatementsofStockholdersEquityDeficitUnaudited" xlink:type="simple" xlink:href="gpgi-20260630.xsd#CondensedConsolidatedStatementsofStockholdersEquityDeficitUnaudited"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/CondensedConsolidatedStatementsofStockholdersEquityDeficitUnaudited" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e65ee-c15a-7e7f-a628-cccf6406f752" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e65ee-c15a-7b39-930d-ad668d18bcd7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-7e7f-a628-cccf6406f752" xlink:to="loc_us-gaap_StatementTable_019e65ee-c15a-7b39-930d-ad668d18bcd7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-779a-8e67-60432dc8c983" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e65ee-c15a-7b39-930d-ad668d18bcd7" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-779a-8e67-60432dc8c983" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-779a-8e67-60432dc8c983_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-779a-8e67-60432dc8c983" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-779a-8e67-60432dc8c983_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-7bf3-9724-8e163c734f5d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15a-779a-8e67-60432dc8c983" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-7bf3-9724-8e163c734f5d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019e65ee-c15a-728e-8527-4275396e890a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e65ee-c15a-7bf3-9724-8e163c734f5d" xlink:to="loc_us-gaap_CommonClassAMember_019e65ee-c15a-728e-8527-4275396e890a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e65ee-c15a-7d8b-844f-2bd04a83e305" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e65ee-c15a-7b39-930d-ad668d18bcd7" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e65ee-c15a-7d8b-844f-2bd04a83e305" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-7d8b-844f-2bd04a83e305_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e65ee-c15a-7d8b-844f-2bd04a83e305" xlink:to="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-7d8b-844f-2bd04a83e305_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e65ee-c15a-7d8b-844f-2bd04a83e305" xlink:to="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e65ee-c15a-7b0d-88c1-b46052e8ae2a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:to="loc_us-gaap_CommonStockMember_019e65ee-c15a-7b0d-88c1-b46052e8ae2a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019e65ee-c15a-7da4-8ddd-3342c37df0c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019e65ee-c15a-7da4-8ddd-3342c37df0c2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019e65ee-c15a-7f6d-8c1f-166845d518c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019e65ee-c15a-7f6d-8c1f-166845d518c4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e65ee-c15a-72ea-bf57-fa32af006150" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e65ee-c15a-72ea-bf57-fa32af006150" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019e65ee-c15a-7c4f-b2ba-7b18c9924bbd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e65ee-c15a-72c9-9527-d72ec91a18b4" xlink:to="loc_us-gaap_RetainedEarningsMember_019e65ee-c15a-7c4f-b2ba-7b18c9924bbd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e65ee-c15a-72a3-9343-ed4fb1c341ff" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e65ee-c15a-7b39-930d-ad668d18bcd7" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e65ee-c15a-72a3-9343-ed4fb1c341ff" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-72a3-9343-ed4fb1c341ff_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e65ee-c15a-72a3-9343-ed4fb1c341ff" xlink:to="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-72a3-9343-ed4fb1c341ff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-7088-9465-97d09ed4a77b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019e65ee-c15a-72a3-9343-ed4fb1c341ff" xlink:to="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-7088-9465-97d09ed4a77b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-780e-9dfc-221cedf9bf9b" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-7088-9465-97d09ed4a77b" xlink:to="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-780e-9dfc-221cedf9bf9b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-7cdb-b376-4b6eccfe341f" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-7088-9465-97d09ed4a77b" xlink:to="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-7cdb-b376-4b6eccfe341f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ResoluteHoldingsMember_019e65ee-c15a-70f3-bb2d-52fe6ab36b3f" xlink:href="gpgi-20260630.xsd#gpgi_ResoluteHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019e65ee-c15a-7088-9465-97d09ed4a77b" xlink:to="loc_gpgi_ResoluteHoldingsMember_019e65ee-c15a-70f3-bb2d-52fe6ab36b3f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e65ee-c15a-7e7f-a628-cccf6406f752" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019e65ee-c15a-70a8-a423-3a08175f8b26" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_SharesOutstanding_019e65ee-c15a-70a8-a423-3a08175f8b26" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e65ee-c15a-74ba-9554-7c4863438fc8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockholdersEquity_019e65ee-c15a-74ba-9554-7c4863438fc8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_019f17b7-571f-74ca-b95c-470fc79ff2b8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_019f17b7-571f-74ca-b95c-470fc79ff2b8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_019f17b7-571f-7753-a7b6-433caae6a2c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_019f17b7-571f-7753-a7b6-433caae6a2c6" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e65ee-c15a-7772-9d90-0baed99f624e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e65ee-c15a-7772-9d90-0baed99f624e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019e65ee-c15a-7e8d-ba2f-8e97525b0df5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019e65ee-c15a-7e8d-ba2f-8e97525b0df5" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_NetIncomeLosses_019e65ee-c15a-7b26-b128-13985fbd0a30" xlink:href="gpgi-20260630.xsd#gpgi_NetIncomeLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_gpgi_NetIncomeLosses_019e65ee-c15a-7b26-b128-13985fbd0a30" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019e65ee-c15a-7f26-bd65-64c53ca9ee2f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019e65ee-c15a-7f26-bd65-64c53ca9ee2f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_019e65ee-c15a-7818-87fc-b7d863d642ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesAcquisitions_019e65ee-c15a-7818-87fc-b7d863d642ce" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_019e65ee-c15a-7db0-9c26-f40f33e5dac4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueAcquisitions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueAcquisitions_019e65ee-c15a-7db0-9c26-f40f33e5dac4" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalDeemedDividendForShareBasedCompensationToResoluteEmployees_019e65ee-c15a-7005-8f33-ca13e82c2647" xlink:href="gpgi-20260630.xsd#gpgi_AdjustmentsToAdditionalPaidInCapitalDeemedDividendForShareBasedCompensationToResoluteEmployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalDeemedDividendForShareBasedCompensationToResoluteEmployees_019e65ee-c15a-7005-8f33-ca13e82c2647" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStock_019e65ee-c15a-767b-abc3-65c430abc64a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_DividendsCommonStock_019e65ee-c15a-767b-abc3-65c430abc64a" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityOther_019fcf53-94e3-720f-a49c-1f8eee8ad0b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityOther"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_StockholdersEquityOther_019fcf53-94e3-720f-a49c-1f8eee8ad0b1" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_019e65ee-c15a-7ebd-860c-acc3245850d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation_019e65ee-c15a-7ebd-860c-acc3245850d3" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019e65ee-c15a-7c10-afa8-8c356e1764fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019e65ee-c15a-7c10-afa8-8c356e1764fa" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_UnrealizedGainLossOnDerivativesInterestRateSwap_019fab9f-031f-797e-87fd-173ec7ba16fe" xlink:href="gpgi-20260630.xsd#gpgi_UnrealizedGainLossOnDerivativesInterestRateSwap"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_gpgi_UnrealizedGainLossOnDerivativesInterestRateSwap_019fab9f-031f-797e-87fd-173ec7ba16fe" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalSpinOff_019e65ee-c15a-70ef-9228-cb8143848317" xlink:href="gpgi-20260630.xsd#gpgi_AdjustmentsToAdditionalPaidInCapitalSpinOff"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalSpinOff_019e65ee-c15a-70ef-9228-cb8143848317" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalDeconsolidation_019e65ee-c15a-7c55-ab25-dce24d1f0b5c" xlink:href="gpgi-20260630.xsd#gpgi_AdjustmentsToAdditionalPaidInCapitalDeconsolidation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e65ee-c15a-7459-a8d3-8c9481eadc79" xlink:to="loc_gpgi_AdjustmentsToAdditionalPaidInCapitalDeconsolidation_019e65ee-c15a-7c55-ab25-dce24d1f0b5c" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharesOutstanding_019e65ee-c15a-7fd3-a4da-dcbe2c7b4692" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e65ee-c15a-72f3-a743-376d0ce71031" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/DESCRIPTIONOFORGANIZATIONANDBUSINESSOPERATIONSDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#DESCRIPTIONOFORGANIZATIONANDBUSINESSOPERATIONSDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/DESCRIPTIONOFORGANIZATIONANDBUSINESSOPERATIONSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_019e65ee-c15a-7f98-8003-0f8d67fa6f80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_ScheduleOfStockByClassTable_019e65ee-c15a-7f98-8003-0f8d67fa6f80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019e65ee-c15a-7906-b592-b02ae851a215" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019e65ee-c15a-7f98-8003-0f8d67fa6f80" xlink:to="loc_srt_CounterpartyNameAxis_019e65ee-c15a-7906-b592-b02ae851a215" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019e65ee-c15a-7906-b592-b02ae851a215_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019e65ee-c15a-7906-b592-b02ae851a215" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019e65ee-c15a-7906-b592-b02ae851a215_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019e65ee-c15a-706a-ab15-20f795bb2b84" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019e65ee-c15a-7906-b592-b02ae851a215" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019e65ee-c15a-706a-ab15-20f795bb2b84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_Tungsten2024LLCMember_019e65ee-c15a-742f-ab76-eeb30a8e7fde" xlink:href="gpgi-20260630.xsd#gpgi_Tungsten2024LLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019e65ee-c15a-706a-ab15-20f795bb2b84" xlink:to="loc_gpgi_Tungsten2024LLCMember_019e65ee-c15a-742f-ab76-eeb30a8e7fde" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019e65ee-c15a-7be5-adac-ee4f913c2704" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019e65ee-c15a-7f98-8003-0f8d67fa6f80" xlink:to="loc_srt_OwnershipAxis_019e65ee-c15a-7be5-adac-ee4f913c2704" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019e65ee-c15a-7be5-adac-ee4f913c2704_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019e65ee-c15a-7be5-adac-ee4f913c2704" xlink:to="loc_srt_OwnershipDomain_019e65ee-c15a-7be5-adac-ee4f913c2704_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019e65ee-c15a-74dd-8e0f-8b793255934e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019e65ee-c15a-7be5-adac-ee4f913c2704" xlink:to="loc_srt_OwnershipDomain_019e65ee-c15a-74dd-8e0f-8b793255934e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-776b-b30b-41470bc61f03" xlink:href="gpgi-20260630.xsd#gpgi_CompoSecureHoldingsL.L.CMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019e65ee-c15a-74dd-8e0f-8b793255934e" xlink:to="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-776b-b30b-41470bc61f03" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e65ee-c15a-78a5-80c9-2449db2c07d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_019e65ee-c15a-7f98-8003-0f8d67fa6f80" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e65ee-c15a-78a5-80c9-2449db2c07d3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e65ee-c15a-78a5-80c9-2449db2c07d3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e65ee-c15a-78a5-80c9-2449db2c07d3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e65ee-c15a-78a5-80c9-2449db2c07d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e65ee-c15a-7a9d-9aed-3b0aa4c253e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e65ee-c15a-78a5-80c9-2449db2c07d3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e65ee-c15a-7a9d-9aed-3b0aa4c253e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-7747-9319-8c18a4c41034" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e65ee-c15a-7a9d-9aed-3b0aa4c253e3" xlink:to="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-7747-9319-8c18a4c41034" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NumberOfOperatingSegments_019e65ee-c15a-7a9a-8fdb-a731c939527f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfOperatingSegments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_NumberOfOperatingSegments_019e65ee-c15a-7a9a-8fdb-a731c939527f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_NumberOfMarketLeadingBusinesses_019e65ee-c15a-7755-82e7-d937aaa5a11d" xlink:href="gpgi-20260630.xsd#gpgi_NumberOfMarketLeadingBusinesses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_NumberOfMarketLeadingBusinesses_019e65ee-c15a-7755-82e7-d937aaa5a11d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_SaleOfStockNumberOfSharesExchangedInTransaction_019e65ee-c15a-71d9-88ae-2b0cc1890a6c" xlink:href="gpgi-20260630.xsd#gpgi_SaleOfStockNumberOfSharesExchangedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_SaleOfStockNumberOfSharesExchangedInTransaction_019e65ee-c15a-71d9-88ae-2b0cc1890a6c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019e65ee-c15a-7b7c-bd0f-a5b5933c6b44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019e65ee-c15a-7b7c-bd0f-a5b5933c6b44" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019e65ee-c15a-7312-8cd0-3bf445039b49" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019e65ee-c15a-7312-8cd0-3bf445039b49" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_019e65ee-c15a-76b8-824d-e6d6a73e7044" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction_019e65ee-c15a-76b8-824d-e6d6a73e7044" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockPricePerShare_019e65ee-c15a-7d66-97b5-7223d0be0a20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_SaleOfStockPricePerShare_019e65ee-c15a-7d66-97b5-7223d0be0a20" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_SaleOfStockPercentageOfOwnershipAcquiredDuringTransaction_019e65ee-c15a-799c-9006-f126eeda58bb" xlink:href="gpgi-20260630.xsd#gpgi_SaleOfStockPercentageOfOwnershipAcquiredDuringTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_SaleOfStockPercentageOfOwnershipAcquiredDuringTransaction_019e65ee-c15a-799c-9006-f126eeda58bb" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_SaleOfStockConversionRatio_019e65ee-c15a-7e69-a515-3891a1071fcf" xlink:href="gpgi-20260630.xsd#gpgi_SaleOfStockConversionRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_SaleOfStockConversionRatio_019e65ee-c15a-7e69-a515-3891a1071fcf" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementFeePercentage_019e65ee-c15a-7c66-883a-bb12466b6c90" xlink:href="gpgi-20260630.xsd#gpgi_ManagementFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_ManagementFeePercentage_019e65ee-c15a-7c66-883a-bb12466b6c90" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementAgreementInitialTerm_019e65ee-c15a-7425-b2ca-48a4b37ccd7e" xlink:href="gpgi-20260630.xsd#gpgi_ManagementAgreementInitialTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_ManagementAgreementInitialTerm_019e65ee-c15a-7425-b2ca-48a4b37ccd7e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementAgreementRenewalTerm_019e65ee-c15a-72d4-827c-59969ff6acdb" xlink:href="gpgi-20260630.xsd#gpgi_ManagementAgreementRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_gpgi_ManagementAgreementRenewalTerm_019e65ee-c15a-72d4-827c-59969ff6acdb" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e65ee-c15a-7ccb-bfb2-d2eb0ad4444b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockLineItems_019e65ee-c15a-7f4b-95ab-fb397ef5184f" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_019e65ee-c15a-7ccb-bfb2-d2eb0ad4444b" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/EQUITYMETHODINVESTMENTNarrativeDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#EQUITYMETHODINVESTMENTNarrativeDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/EQUITYMETHODINVESTMENTNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-730c-916f-7fe451b82bd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7df2-9069-6950921632b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-730c-916f-7fe451b82bd3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7df2-9069-6950921632b7" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7473-93a1-1f4788494adb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7df2-9069-6950921632b7" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7473-93a1-1f4788494adb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7473-93a1-1f4788494adb_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7473-93a1-1f4788494adb" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7473-93a1-1f4788494adb_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-71cc-9f69-b911e01baaef" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7473-93a1-1f4788494adb" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-71cc-9f69-b911e01baaef" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-7ca9-ae13-eff51ab81af2" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-71cc-9f69-b911e01baaef" xlink:to="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-7ca9-ae13-eff51ab81af2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-79b8-b3d8-1d61fb7429a0" xlink:href="gpgi-20260630.xsd#gpgi_CompoSecureHoldingsL.L.CMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-71cc-9f69-b911e01baaef" xlink:to="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-79b8-b3d8-1d61fb7429a0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-73f5-8f04-3c6629e738d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7df2-9069-6950921632b7" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-73f5-8f04-3c6629e738d8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-73f5-8f04-3c6629e738d8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-73f5-8f04-3c6629e738d8" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-73f5-8f04-3c6629e738d8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7d36-822a-4d78f6b2d6ba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-73f5-8f04-3c6629e738d8" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7d36-822a-4d78f6b2d6ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-7a47-8391-28c6a63856e3" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7d36-822a-4d78f6b2d6ba" xlink:to="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-7a47-8391-28c6a63856e3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019e65ee-c15a-7106-93b6-c8d9ee39db8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-730c-916f-7fe451b82bd3" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019e65ee-c15a-7106-93b6-c8d9ee39db8e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-743f-8670-94f62092f83d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-730c-916f-7fe451b82bd3" xlink:to="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-743f-8670-94f62092f83d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e65ee-c15a-7a0b-8c7b-ae530aef236f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-730c-916f-7fe451b82bd3" xlink:to="loc_us-gaap_Liabilities_019e65ee-c15a-7a0b-8c7b-ae530aef236f" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/EQUITYMETHODINVESTMENTSpinOffandDeconsolidationDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#EQUITYMETHODINVESTMENTSpinOffandDeconsolidationDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/EQUITYMETHODINVESTMENTSpinOffandDeconsolidationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7b6c-b8e8-ad6eb96f3d3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7b6c-b8e8-ad6eb96f3d3c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-7c98-8056-c5a21589d19d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7b6c-b8e8-ad6eb96f3d3c" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-7c98-8056-c5a21589d19d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7c98-8056-c5a21589d19d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-7c98-8056-c5a21589d19d" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7c98-8056-c5a21589d19d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7dea-b891-e287a2d50ebe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeAxis_019e65ee-c15a-7c98-8056-c5a21589d19d" xlink:to="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7dea-b891-e287a2d50ebe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-72ff-94e0-5e1f24cfca06" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityMethodInvestmentNonconsolidatedInvesteeDomain_019e65ee-c15a-7dea-b891-e287a2d50ebe" xlink:to="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-72ff-94e0-5e1f24cfca06" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e65ee-c15a-7dfd-8161-504efe31d375" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e65ee-c15a-7dfd-8161-504efe31d375" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019e65ee-c15a-76c1-b919-7a28ac3223f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019e65ee-c15a-76c1-b919-7a28ac3223f2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_019e65ee-c15a-77ff-8dcc-751a62ccf41e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_GrossProfit_019e65ee-c15a-77ff-8dcc-751a62ccf41e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpensesAbstract_019e65ee-c15a-75b9-ae64-f57455e06c9a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_OperatingExpensesAbstract_019e65ee-c15a-75b9-ae64-f57455e06c9a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_019e65ee-c15a-75a6-9894-239eeab53cea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019e65ee-c15a-75b9-ae64-f57455e06c9a" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_019e65ee-c15a-75a6-9894-239eeab53cea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_019e65ee-c15a-7f9c-a2ce-43ec2e1c5bbe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_019e65ee-c15a-75b9-ae64-f57455e06c9a" xlink:to="loc_us-gaap_OperatingIncomeLoss_019e65ee-c15a-7f9c-a2ce-43ec2e1c5bbe" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherIncomeAndExpensesAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019e65ee-c15a-78d0-a093-c46c49aec8d5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019e65ee-c15a-78d0-a093-c46c49aec8d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_019e65ee-c15a-70db-8718-4d3d5276537f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:to="loc_us-gaap_InvestmentIncomeInterest_019e65ee-c15a-70db-8718-4d3d5276537f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019e65ee-c15a-7818-a32d-3ed534650aae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019e65ee-c15a-7818-a32d-3ed534650aae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_019e65ee-c15a-739c-97f8-0c7bc25857c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherIncomeAndExpensesAbstract_019e65ee-c15a-7dfd-97d0-883c4a4224bc" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_019e65ee-c15a-739c-97f8-0c7bc25857c9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossAttributableToParent_019e65ee-c15a-7997-8ab4-f19c12ca50c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_IncomeLossAttributableToParent_019e65ee-c15a-7997-8ab4-f19c12ca50c8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019e65ee-c15a-7fdc-9189-caaa9f7a29bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019e65ee-c15a-7fdc-9189-caaa9f7a29bb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e65ee-c15a-7e8a-b2fe-aec1ff24c72a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-76f5-8a1f-acfd10d9ebf7" xlink:to="loc_us-gaap_NetIncomeLoss_019e65ee-c15a-7e8a-b2fe-aec1ff24c72a" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/EQUITYMETHODINVESTMENTReconciliationoftheCompanysEquityMethodInvestmentsDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#EQUITYMETHODINVESTMENTReconciliationoftheCompanysEquityMethodInvestmentsDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/EQUITYMETHODINVESTMENTReconciliationoftheCompanysEquityMethodInvestmentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-7676-86d3-b00f00112bd1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7644-8381-e2a71cb8b134" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-7676-86d3-b00f00112bd1" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7644-8381-e2a71cb8b134" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7ddb-aaf8-501b5f63dc31" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleTable_019e65ee-c15a-7644-8381-e2a71cb8b134" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7ddb-aaf8-501b5f63dc31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7ddb-aaf8-501b5f63dc31_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7ddb-aaf8-501b5f63dc31" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7ddb-aaf8-501b5f63dc31_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7332-9b05-8d3c941bce23" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e65ee-c15a-7ddb-aaf8-501b5f63dc31" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7332-9b05-8d3c941bce23" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-70e0-ad42-9772de535f48" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e65ee-c15a-7332-9b05-8d3c941bce23" xlink:to="loc_gpgi_GPGIHoldingsMember_019e65ee-c15a-70e0-ad42-9772de535f48" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_019e65ee-c15a-7676-86d3-b00f00112bd1" xlink:to="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-7fcc-bc6d-4b43127ba6a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-7fcc-bc6d-4b43127ba6a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsStockBasedCompensation_019e65ee-c15a-708c-8cc7-7bec6e85fd72" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsStockBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsStockBasedCompensation_019e65ee-c15a-708c-8cc7-7bec6e85fd72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsEarningsLosses_019e65ee-c15a-7aaa-9177-6ed9760c6a3b" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsEarningsLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsEarningsLosses_019e65ee-c15a-7aaa-9177-6ed9760c6a3b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsCashTransaction_019fb824-3470-71b1-bf84-87ef8a732863" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsCashTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsCashTransaction_019fb824-3470-71b1-bf84-87ef8a732863" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsEquityTransaction_019e65ee-c15a-7beb-9a48-c809b977196f" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsEquityTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsEquityTransaction_019e65ee-c15a-7beb-9a48-c809b977196f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsContribution_019fb82d-b057-75b1-b5ce-2d76332165b2" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsContribution"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsContribution_019fb82d-b057-75b1-b5ce-2d76332165b2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EquityMethodInvestmentsAdvanceToAffiliate_019e65ee-c15a-7fb9-968b-88e314a34e96" xlink:href="gpgi-20260630.xsd#gpgi_EquityMethodInvestmentsAdvanceToAffiliate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_EquityMethodInvestmentsRollForward_019e65ee-c15a-77b4-b0ee-9bd7ef301fd7" xlink:to="loc_gpgi_EquityMethodInvestmentsAdvanceToAffiliate_019e65ee-c15a-7fb9-968b-88e314a34e96" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e65ee-c15a-74d4-bdf8-280d71213903" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/EQUITYSTRUCTUREDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#EQUITYSTRUCTUREDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/EQUITYSTRUCTUREDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019faba8-b721-7e3d-83f0-87bdcd65eb1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019faba8-b721-7e3d-83f0-87bdcd65eb1e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019faba8-b721-7e3d-83f0-87bdcd65eb1e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019faba8-b721-7e3d-83f0-87bdcd65eb1e" xlink:to="loc_us-gaap_ClassOfStockDomain_019faba8-b721-7e3d-83f0-87bdcd65eb1e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019faba8-b721-7932-aefb-a08cb6548884" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019faba8-b721-7e3d-83f0-87bdcd65eb1e" xlink:to="loc_us-gaap_ClassOfStockDomain_019faba8-b721-7932-aefb-a08cb6548884" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019faba8-b721-7c82-a30b-314ea423dce9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019faba8-b721-7932-aefb-a08cb6548884" xlink:to="loc_us-gaap_CommonClassAMember_019faba8-b721-7c82-a30b-314ea423dce9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019faba8-c916-7641-84de-a7cec78e8f33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019faba8-c916-7641-84de-a7cec78e8f33" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019faba8-c916-7641-84de-a7cec78e8f33_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019faba8-c916-7641-84de-a7cec78e8f33" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019faba8-c916-7641-84de-a7cec78e8f33_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019faba8-c916-71cb-bc65-dd38c538ba7c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019faba8-c916-7641-84de-a7cec78e8f33" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019faba8-c916-71cb-bc65-dd38c538ba7c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019faba8-c916-7a83-a2bb-30ab63844836" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019faba8-c916-71cb-bc65-dd38c538ba7c" xlink:to="loc_gpgi_HuskyHoldingsMember_019faba8-c916-7a83-a2bb-30ab63844836" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis_019faba8-c916-7595-8dca-953ca14c5837" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:to="loc_us-gaap_SubsidiarySaleOfStockAxis_019faba8-c916-7595-8dca-953ca14c5837" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019faba8-c916-7595-8dca-953ca14c5837_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019faba8-c916-7595-8dca-953ca14c5837" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019faba8-c916-7595-8dca-953ca14c5837_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019faba8-c916-723c-aaad-c9a3cebebcd5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis_019faba8-c916-7595-8dca-953ca14c5837" xlink:to="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019faba8-c916-723c-aaad-c9a3cebebcd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PIPEPurchaseAgreementMember_019faba8-c916-78fa-9324-95846d52b56b" xlink:href="gpgi-20260630.xsd#gpgi_PIPEPurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain_019faba8-c916-723c-aaad-c9a3cebebcd5" xlink:to="loc_gpgi_PIPEPurchaseAgreementMember_019faba8-c916-78fa-9324-95846d52b56b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis_019faba8-de3d-7bd8-bf23-c03cc668e234" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable_019e65ee-c15a-7892-8204-63a181632de2" xlink:to="loc_us-gaap_ClassOfWarrantOrRightAxis_019faba8-de3d-7bd8-bf23-c03cc668e234" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_019faba8-de3d-7bd8-bf23-c03cc668e234_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_019faba8-de3d-7bd8-bf23-c03cc668e234" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_019faba8-de3d-7bd8-bf23-c03cc668e234_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain_019faba8-de3d-72ac-acc0-f4e48223a452" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis_019faba8-de3d-7bd8-bf23-c03cc668e234" xlink:to="loc_us-gaap_ClassOfWarrantOrRightDomain_019faba8-de3d-72ac-acc0-f4e48223a452" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_WarrantsMember_019faba8-de3d-738c-9c0b-45b30a69af89" xlink:href="gpgi-20260630.xsd#gpgi_WarrantsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain_019faba8-de3d-72ac-acc0-f4e48223a452" xlink:to="loc_gpgi_WarrantsMember_019faba8-de3d-738c-9c0b-45b30a69af89" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_019faba8-b721-7425-b43d-835a675a18b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_CommonStockSharesAuthorized_019faba8-b721-7425-b43d-835a675a18b5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare_019faba8-b721-7c7e-9065-3963a4291530" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_CommonStockParOrStatedValuePerShare_019faba8-b721-7c7e-9065-3963a4291530" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConversionOfStockSharesConverted1_019faba8-b721-7b0c-8233-3d73655dc8e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConversionOfStockSharesConverted1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_ConversionOfStockSharesConverted1_019faba8-b721-7b0c-8233-3d73655dc8e4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019faba8-c916-7a8e-bab3-a9e0fe47b182" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_019faba8-c916-7a8e-bab3-a9e0fe47b182" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_019faba8-c916-75db-961f-74ffee278232" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_BusinessAcquisitionEquityInterestsIssuedOrIssuableNumberOfSharesIssued_019faba8-c916-75db-961f-74ffee278232" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019faba8-c916-7953-9ed1-ecb23e7ff6c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction_019faba8-c916-7953-9ed1-ecb23e7ff6c1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_WarrantsOrRightsOutstandingRedemptionPricePerShare_019faba8-de3d-777f-b22f-d6b54a77d61e" xlink:href="gpgi-20260630.xsd#gpgi_WarrantsOrRightsOutstandingRedemptionPricePerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_gpgi_WarrantsOrRightsOutstandingRedemptionPricePerShare_019faba8-de3d-777f-b22f-d6b54a77d61e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019fabac-9c77-7e1f-b81a-915221acfba0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_ClassOfWarrantOrRightOutstanding_019fabac-9c77-7e1f-b81a-915221acfba0" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCash_019faba8-ef45-7031-a6ab-97e3d0aee215" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_DividendsCash_019faba8-ef45-7031-a6ab-97e3d0aee215" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019faba9-0825-7203-ac27-8fb077a4ab40" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019faba9-0825-7203-ac27-8fb077a4ab40" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019faba9-0825-7bfa-9a64-75a33df13d70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019faba9-0825-7bfa-9a64-75a33df13d70" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_019faba9-0825-73e2-a249-13387dc53095" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems_019faba8-b721-7011-9b86-4715c063ed51" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_019faba9-0825-73e2-a249-13387dc53095" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/STOCKBASEDCOMPENSATIONNarrativeDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#STOCKBASEDCOMPENSATIONNarrativeDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/STOCKBASEDCOMPENSATIONNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019fabae-e6e2-78c2-a416-bc52bd7cb719" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:to="loc_us-gaap_AwardTypeAxis_019fabae-e6e2-78c2-a416-bc52bd7cb719" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-78c2-a416-bc52bd7cb719_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019fabae-e6e2-78c2-a416-bc52bd7cb719" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-78c2-a416-bc52bd7cb719_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019fabae-e6e2-78c2-a416-bc52bd7cb719" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ContractorAgreementsMember_019fabae-e6e2-71a7-ad2a-7884a6fe3e33" xlink:href="gpgi-20260630.xsd#gpgi_ContractorAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:to="loc_gpgi_ContractorAgreementsMember_019fabae-e6e2-71a7-ad2a-7884a6fe3e33" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019fabaf-0bdd-79f0-bb78-fe6d2fd655e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019fabaf-0bdd-79f0-bb78-fe6d2fd655e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_019fabaf-347a-744d-9c0d-aa4749a80c90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:to="loc_us-gaap_PerformanceSharesMember_019fabaf-347a-744d-9c0d-aa4749a80c90" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019fabaf-66ad-7eba-8799-8e1c25145afa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019fabaf-66ad-7eba-8799-8e1c25145afa" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_LongTermIncentivePlanAwardsMember_019fabaf-66ad-7ab7-9975-c3da9e4a0927" xlink:href="gpgi-20260630.xsd#gpgi_LongTermIncentivePlanAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019fabae-e6e2-7985-abff-0ed0a84219e1" xlink:to="loc_gpgi_LongTermIncentivePlanAwardsMember_019fabaf-66ad-7ab7-9975-c3da9e4a0927" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019fabae-e6e2-79a7-a9fe-57744b82f87d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019fabae-e6e2-79a7-a9fe-57744b82f87d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019fabae-e6e2-79a7-a9fe-57744b82f87d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019fabae-e6e2-79a7-a9fe-57744b82f87d" xlink:to="loc_us-gaap_EquityComponentDomain_019fabae-e6e2-79a7-a9fe-57744b82f87d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019fabae-e6e2-790b-a0b8-62401ec89eb2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019fabae-e6e2-79a7-a9fe-57744b82f87d" xlink:to="loc_us-gaap_EquityComponentDomain_019fabae-e6e2-790b-a0b8-62401ec89eb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019fabae-e6e2-71ba-b2c9-4970b753af6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019fabae-e6e2-790b-a0b8-62401ec89eb2" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019fabae-e6e2-71ba-b2c9-4970b753af6a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fabaf-66ad-7697-8aca-8bd576830e98" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:to="loc_srt_CounterpartyNameAxis_019fabaf-66ad-7697-8aca-8bd576830e98" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-7697-8aca-8bd576830e98_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019fabaf-66ad-7697-8aca-8bd576830e98" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-7697-8aca-8bd576830e98_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-70b1-b6c1-8dc768b1fdfe" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019fabaf-66ad-7697-8aca-8bd576830e98" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-70b1-b6c1-8dc768b1fdfe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GPGIHoldingsMember_019fabb1-89c0-733f-b685-d2c2e832a413" xlink:href="gpgi-20260630.xsd#gpgi_GPGIHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-70b1-b6c1-8dc768b1fdfe" xlink:to="loc_gpgi_GPGIHoldingsMember_019fabb1-89c0-733f-b685-d2c2e832a413" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019fabaf-66ad-7e41-9017-ad80464e33dd" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabaf-66ad-70b1-b6c1-8dc768b1fdfe" xlink:to="loc_gpgi_HuskyHoldingsMember_019fabaf-66ad-7e41-9017-ad80464e33dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramPeriodAxis_019fabaf-66ad-7d81-a6ed-0a4581588353" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-710c-9bb4-ff5e509c3e51" xlink:to="loc_gpgi_PerformanceIncentiveProgramPeriodAxis_019fabaf-66ad-7d81-a6ed-0a4581588353" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7d81-a6ed-0a4581588353_default" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodAxis_019fabaf-66ad-7d81-a6ed-0a4581588353" xlink:to="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7d81-a6ed-0a4581588353_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodAxis_019fabaf-66ad-7d81-a6ed-0a4581588353" xlink:to="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_A2026TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-7eab-8282-3fcd2d19ede5" xlink:href="gpgi-20260630.xsd#gpgi_A2026TargetHuskyAdjustedEBITDAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:to="loc_gpgi_A2026TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-7eab-8282-3fcd2d19ede5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_A2027TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-718d-a86a-53fa585d8cf3" xlink:href="gpgi-20260630.xsd#gpgi_A2027TargetHuskyAdjustedEBITDAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:to="loc_gpgi_A2027TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-718d-a86a-53fa585d8cf3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_A2028TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-7b23-9768-e5de8e136eaf" xlink:href="gpgi-20260630.xsd#gpgi_A2028TargetHuskyAdjustedEBITDAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:to="loc_gpgi_A2028TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-7b23-9768-e5de8e136eaf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_A2029TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-73c0-b0ac-7ee0b90e3047" xlink:href="gpgi-20260630.xsd#gpgi_A2029TargetHuskyAdjustedEBITDAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_gpgi_PerformanceIncentiveProgramPeriodDomain_019fabaf-66ad-7a75-b4f6-788424af9219" xlink:to="loc_gpgi_A2029TargetHuskyAdjustedEBITDAMember_019fabaf-66ad-73c0-b0ac-7ee0b90e3047" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PercentageOfAggregateNumberOfShares_019fabae-c4c1-7284-aa03-72c49d958d84" xlink:href="gpgi-20260630.xsd#gpgi_PercentageOfAggregateNumberOfShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_gpgi_PercentageOfAggregateNumberOfShares_019fabae-c4c1-7284-aa03-72c49d958d84" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_019fabae-e6e2-7abf-84ac-3dfe48eabb37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_019fabae-e6e2-7abf-84ac-3dfe48eabb37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019fabae-e6e2-7229-9b0b-33e7256cff05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019fabae-e6e2-7229-9b0b-33e7256cff05" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019fabaf-0bdd-762b-a501-b3836ef8e328" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions_019fabaf-0bdd-762b-a501-b3836ef8e328" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019fabaf-0bdd-776f-8b51-7711e50a40a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_019fabaf-0bdd-776f-8b51-7711e50a40a5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019fabaf-347a-76e7-ac7f-1bace007ea50" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019fabaf-347a-76e7-ac7f-1bace007ea50" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019fabaf-66ad-7e4a-bdd9-fa9467f366da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019fabaf-66ad-7e4a-bdd9-fa9467f366da" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationDuration_019fabaf-66ad-7c69-8fd5-48e41322f64c" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationDuration"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationDuration_019fabaf-66ad-7c69-8fd5-48e41322f64c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization_019fabaf-66ad-7f83-b2d8-cc0018df12a4" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization_019fabaf-66ad-7f83-b2d8-cc0018df12a4" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardPercentage_019fabaf-81b5-788e-a739-5c347731b7d9" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardPercentage_019fabaf-81b5-788e-a739-5c347731b7d9" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardValue_019fabaf-81b5-73eb-8b4f-64422cfadb54" xlink:href="gpgi-20260630.xsd#gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019fabae-c4c1-7f7b-804b-ea383ea25feb" xlink:to="loc_gpgi_PerformanceIncentiveProgramAdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationTargetAwardValue_019fabaf-81b5-73eb-8b4f-64422cfadb54" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/STOCKBASEDCOMPENSATIONStockBasedCompensationExpenseDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#STOCKBASEDCOMPENSATIONStockBasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/STOCKBASEDCOMPENSATIONStockBasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-7dd9-9dfa-714ee0f1b597" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77b5-8086-51b6367b3fa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-7dd9-9dfa-714ee0f1b597" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77b5-8086-51b6367b3fa3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7b28-a5aa-923ba753a9c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77b5-8086-51b6367b3fa3" xlink:to="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7b28-a5aa-923ba753a9c4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7b28-a5aa-923ba753a9c4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7b28-a5aa-923ba753a9c4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7b28-a5aa-923ba753a9c4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-71c8-92ff-b93b2f158427" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7b28-a5aa-923ba753a9c4" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-71c8-92ff-b93b2f158427" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019e65ee-c15a-70b6-b2ae-284802db51d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-71c8-92ff-b93b2f158427" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019e65ee-c15a-70b6-b2ae-284802db51d7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PerformanceSharesMember_019e65ee-c15a-73cf-a8c1-b170be70e8c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-71c8-92ff-b93b2f158427" xlink:to="loc_us-gaap_PerformanceSharesMember_019e65ee-c15a-73cf-a8c1-b170be70e8c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019e65ee-c15a-739a-bc0e-0553828d88fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-71c8-92ff-b93b2f158427" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019e65ee-c15a-739a-bc0e-0553828d88fa" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e65ee-c15a-78fb-9b75-2f33942dcf6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-7dd9-9dfa-714ee0f1b597" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e65ee-c15a-78fb-9b75-2f33942dcf6c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/STOCKBASEDCOMPENSATIONRSUActivityUndertheEquityPlanDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#STOCKBASEDCOMPENSATIONRSUActivityUndertheEquityPlanDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/STOCKBASEDCOMPENSATIONRSUActivityUndertheEquityPlanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f4774-1f9c-797d-ba29-a5db5ff8b485" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f4774-1f9c-7011-8e0c-f846ed88f38c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f4774-1f9c-797d-ba29-a5db5ff8b485" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f4774-1f9c-7011-8e0c-f846ed88f38c" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019f4774-1f9c-7133-8db9-84210b5c2217" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f4774-1f9c-7011-8e0c-f846ed88f38c" xlink:to="loc_us-gaap_AwardTypeAxis_019f4774-1f9c-7133-8db9-84210b5c2217" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f4774-1f9c-7133-8db9-84210b5c2217_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019f4774-1f9c-7133-8db9-84210b5c2217" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f4774-1f9c-7133-8db9-84210b5c2217_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f4774-1f9c-7f82-a2e9-5b66943d7b92" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019f4774-1f9c-7133-8db9-84210b5c2217" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f4774-1f9c-7f82-a2e9-5b66943d7b92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019f4774-1f9c-74e3-80ac-2c44a1e0433c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f4774-1f9c-7f82-a2e9-5b66943d7b92" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019f4774-1f9c-74e3-80ac-2c44a1e0433c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f4774-1f9c-797d-ba29-a5db5ff8b485" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019f4774-1f9c-7b87-94fe-105789201b3b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019f4774-1f9c-7b87-94fe-105789201b3b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019f4774-1f9c-79c7-be98-81d53510fc60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_019f4774-1f9c-79c7-be98-81d53510fc60" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019f4774-1f9c-7632-83a5-2bda01863b04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_019f4774-1f9c-7632-83a5-2bda01863b04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019f4774-1f9c-7a3f-afc5-4977fe8b3d47" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward_019f4775-75f1-7d2b-955a-671743145b94" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_019f4774-1f9c-7a3f-afc5-4977fe8b3d47" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_019f4774-6126-7371-86c5-cd5a7022938e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/STOCKBASEDCOMPENSATIONValueoftheOptionsGrantedDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#STOCKBASEDCOMPENSATIONValueoftheOptionsGrantedDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/STOCKBASEDCOMPENSATIONValueoftheOptionsGrantedDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77d6-be56-bd2d810c62b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77d6-be56-bd2d810c62b1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7f75-976e-6489f91f748f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e65ee-c15a-77d6-be56-bd2d810c62b1" xlink:to="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7f75-976e-6489f91f748f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7f75-976e-6489f91f748f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7f75-976e-6489f91f748f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7f75-976e-6489f91f748f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7e2f-8590-0f684d50364c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019e65ee-c15a-7f75-976e-6489f91f748f" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7e2f-8590-0f684d50364c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019e65ee-c15a-7ee9-bf08-ef5c381835cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e65ee-c15a-7e2f-8590-0f684d50364c" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019e65ee-c15a-7ee9-bf08-ef5c381835cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019e65ee-c15a-7a52-91c0-6ef729169efb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1_019e65ee-c15a-7a52-91c0-6ef729169efb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019e65ee-c15a-7828-a8ae-2958ed72ed6e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate_019e65ee-c15a-7828-a8ae-2958ed72ed6e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019e65ee-c15a-7405-aec9-d12ea570b37c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate_019e65ee-c15a-7405-aec9-d12ea570b37c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_019e65ee-c15a-7a21-8ed4-288d02bb3931" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate_019e65ee-c15a-7a21-8ed4-288d02bb3931" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue_019f1702-5417-7946-b0bd-a962149b090a" xlink:href="gpgi-20260630.xsd#gpgi_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e65ee-c15a-75f0-8fe5-ee0c4a2e5f5b" xlink:to="loc_gpgi_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageGrantDateFairValue_019f1702-5417-7946-b0bd-a962149b090a" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/STOCKBASEDCOMPENSATIONOptionsActivityUndertheEquityPlanDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#STOCKBASEDCOMPENSATIONOptionsActivityUndertheEquityPlanDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/STOCKBASEDCOMPENSATIONOptionsActivityUndertheEquityPlanDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f475a-7d7e-742d-8d2e-d6a62de8a504" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f475a-7d7e-7cec-bcda-7e11af11bab4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f475a-7d7e-742d-8d2e-d6a62de8a504" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f475a-7d7e-7cec-bcda-7e11af11bab4" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019f475a-7d7e-74cb-a891-51abc0166132" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019f475a-7d7e-7cec-bcda-7e11af11bab4" xlink:to="loc_us-gaap_AwardTypeAxis_019f475a-7d7e-74cb-a891-51abc0166132" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f475a-7d7e-74cb-a891-51abc0166132_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019f475a-7d7e-74cb-a891-51abc0166132" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f475a-7d7e-74cb-a891-51abc0166132_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f475a-7d7e-7791-b8e4-398c1a995fcb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019f475a-7d7e-74cb-a891-51abc0166132" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f475a-7d7e-7791-b8e4-398c1a995fcb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019f4772-ffc9-7821-bdd0-1552599d9bd8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019f475a-7d7e-7791-b8e4-398c1a995fcb" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019f4772-ffc9-7821-bdd0-1552599d9bd8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f475a-7d7e-742d-8d2e-d6a62de8a504" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019f475a-7d7e-7938-b290-9b9d7c453df5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019f475a-7d7e-7938-b290-9b9d7c453df5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019f475b-de8f-7ef0-a01c-c10ad4114233" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_019f475b-de8f-7ef0-a01c-c10ad4114233" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019f475a-7d7e-7628-8b78-220894a50242" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019f475a-7d7e-7628-8b78-220894a50242" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_019f475a-7d7e-7a11-99bd-e75017dbba4b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_019f475b-498b-752f-8dbf-28de9f0b6b9e" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_019f475a-7d7e-7a11-99bd-e75017dbba4b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_019f475c-8ceb-7668-9a80-8f9b5450a207" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019f475a-7d7e-742d-8d2e-d6a62de8a504" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019f476e-7802-70ac-bcd3-e904591d005a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019f476e-7802-70ac-bcd3-e904591d005a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_019f476e-7802-7d64-b6c8-26a7e199aedc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_019f476e-7802-7d64-b6c8-26a7e199aedc" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_019f476e-7802-783a-8a32-3b725c5ba621" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_019f476e-7802-783a-8a32-3b725c5ba621" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_019f476e-7802-7581-9295-3bf4c107f69f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_019f476e-2d9f-783e-9f85-1e5c6187ec91" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_019f476e-7802-7581-9295-3bf4c107f69f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_019f476f-16ed-7d79-8da1-f92c400685bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/NETINCOMELOSSPERSHAREComputationofDilutedNetIncomeLossPerShareofCommonStockBecauseTheirEffectwasAntiDilutiveDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#NETINCOMELOSSPERSHAREComputationofDilutedNetIncomeLossPerShareofCommonStockBecauseTheirEffectwasAntiDilutiveDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/NETINCOMELOSSPERSHAREComputationofDilutedNetIncomeLossPerShareofCommonStockBecauseTheirEffectwasAntiDilutiveDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e65ee-c15a-7b19-ae0c-2fd77c485ad0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e65ee-c15a-7063-9fc3-4b95011eaa07" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e65ee-c15a-7b19-ae0c-2fd77c485ad0" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e65ee-c15a-7063-9fc3-4b95011eaa07" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e65ee-c15a-71e7-a494-64d2e3347225" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e65ee-c15a-7063-9fc3-4b95011eaa07" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e65ee-c15a-71e7-a494-64d2e3347225" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-71e7-a494-64d2e3347225_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e65ee-c15a-71e7-a494-64d2e3347225" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-71e7-a494-64d2e3347225_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-7c7a-b6ab-1c8e778bd961" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e65ee-c15a-71e7-a494-64d2e3347225" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-7c7a-b6ab-1c8e778bd961" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_019e65ee-c15a-7487-b798-9427b7241e44" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-7c7a-b6ab-1c8e778bd961" xlink:to="loc_us-gaap_WarrantMember_019e65ee-c15a-7487-b798-9427b7241e44" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_EarnoutConsiderationMember_019e65ee-c15a-7cf2-88da-0383972559be" xlink:href="gpgi-20260630.xsd#gpgi_EarnoutConsiderationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-7c7a-b6ab-1c8e778bd961" xlink:to="loc_gpgi_EarnoutConsiderationMember_019e65ee-c15a-7cf2-88da-0383972559be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockCompensationPlanMember_019e65ee-c15a-715f-9dcc-1428f0444902" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockCompensationPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e65ee-c15a-7c7a-b6ab-1c8e778bd961" xlink:to="loc_us-gaap_StockCompensationPlanMember_019e65ee-c15a-715f-9dcc-1428f0444902" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e65ee-c15a-7525-b645-155d4dccfabc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e65ee-c15a-7b19-ae0c-2fd77c485ad0" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e65ee-c15a-7525-b645-155d4dccfabc" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/SEGMENTREPORTINGSegmentReportingInformationbySegmentDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#SEGMENTREPORTINGSegmentReportingInformationbySegmentDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/SEGMENTREPORTINGSegmentReportingInformationbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e65ee-c15a-7c95-a104-072818b7c92e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e65ee-c15a-7c95-a104-072818b7c92e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019e65ee-c15a-79dc-80d9-0d694f02778c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e65ee-c15a-7c95-a104-072818b7c92e" xlink:to="loc_srt_ConsolidationItemsAxis_019e65ee-c15a-79dc-80d9-0d694f02778c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-79dc-80d9-0d694f02778c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019e65ee-c15a-79dc-80d9-0d694f02778c" xlink:to="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-79dc-80d9-0d694f02778c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-7395-b398-50482aee0af0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019e65ee-c15a-79dc-80d9-0d694f02778c" xlink:to="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-7395-b398-50482aee0af0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019e65ee-c15a-77ca-a75d-b03f2cd47e37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-7395-b398-50482aee0af0" xlink:to="loc_us-gaap_OperatingSegmentsMember_019e65ee-c15a-77ca-a75d-b03f2cd47e37" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_019e65ee-c15a-73c9-887b-c393a87e875f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e65ee-c15a-7395-b398-50482aee0af0" xlink:to="loc_us-gaap_IntersegmentEliminationMember_019e65ee-c15a-73c9-887b-c393a87e875f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e65ee-c15a-7e70-a03e-b74d8d0faa53" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e65ee-c15a-7c95-a104-072818b7c92e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e65ee-c15a-7e70-a03e-b74d8d0faa53" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e65ee-c15a-7e70-a03e-b74d8d0faa53_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e65ee-c15a-7e70-a03e-b74d8d0faa53" xlink:to="loc_us-gaap_SegmentDomain_019e65ee-c15a-7e70-a03e-b74d8d0faa53_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e65ee-c15a-7cd1-aa0c-7177e5535d6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e65ee-c15a-7e70-a03e-b74d8d0faa53" xlink:to="loc_us-gaap_SegmentDomain_019e65ee-c15a-7cd1-aa0c-7177e5535d6a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-7621-86a9-5761e2dc3763" xlink:href="gpgi-20260630.xsd#gpgi_CompoSecureHoldingsL.L.CMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e65ee-c15a-7cd1-aa0c-7177e5535d6a" xlink:to="loc_gpgi_CompoSecureHoldingsL.L.CMember_019e65ee-c15a-7621-86a9-5761e2dc3763" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-701c-b429-688b4899af92" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e65ee-c15a-7cd1-aa0c-7177e5535d6a" xlink:to="loc_gpgi_HuskyHoldingsMember_019e65ee-c15a-701c-b429-688b4899af92" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e65ee-c15a-7236-b61d-04992387ece7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e65ee-c15a-7236-b61d-04992387ece7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_Material_019e65ee-c15a-7137-beaf-19a9378cd3d4" xlink:href="gpgi-20260630.xsd#gpgi_Material"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_Material_019e65ee-c15a-7137-beaf-19a9378cd3d4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_Personnel_019e65ee-c15a-708e-ad9e-89a4778ca5a3" xlink:href="gpgi-20260630.xsd#gpgi_Personnel"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_Personnel_019e65ee-c15a-708e-ad9e-89a4778ca5a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_019e65ee-c15a-739b-8a22-61ad138018a1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSoldOverhead"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSoldOverhead_019e65ee-c15a-739b-8a22-61ad138018a1" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfessionalFees_019e65ee-c15a-7276-9bed-ca6f9c0d0c51" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfessionalFees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_ProfessionalFees_019e65ee-c15a-7276-9bed-ca6f9c0d0c51" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_019e65ee-c15a-791f-9bb4-e20bb1597084" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_ManagementFeeExpense_019e65ee-c15a-791f-9bb4-e20bb1597084" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_SalesAndMarketingExpenses_019e65ee-c15a-7356-8490-7392edde7f65" xlink:href="gpgi-20260630.xsd#gpgi_SalesAndMarketingExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_SalesAndMarketingExpenses_019e65ee-c15a-7356-8490-7392edde7f65" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_019e65ee-c15a-7e33-83c7-d559058fd234" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_019e65ee-c15a-7e33-83c7-d559058fd234" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_NetIncomeLossAttributableToParentAdjustedEBITDA_019e65ee-c15a-7a1b-99b3-b599cafba115" xlink:href="gpgi-20260630.xsd#gpgi_NetIncomeLossAttributableToParentAdjustedEBITDA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_NetIncomeLossAttributableToParentAdjustedEBITDA_019e65ee-c15a-7a1b-99b3-b599cafba115" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CorporateAdjustedEBITDA_019e65ee-c15a-7fcf-8a1c-eb973a66cc8d" xlink:href="gpgi-20260630.xsd#gpgi_CorporateAdjustedEBITDA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_CorporateAdjustedEBITDA_019e65ee-c15a-7fcf-8a1c-eb973a66cc8d" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_019e65ee-c15a-7066-8cc9-228565eb51e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_019e65ee-c15a-7066-8cc9-228565eb51e1" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_019e65ee-c15a-767f-894b-1d377895a5c2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeBenefitsAndShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_EmployeeBenefitsAndShareBasedCompensation_019e65ee-c15a-767f-894b-1d377895a5c2" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_019e65ee-c15a-727e-b3cb-43f791e43ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_019e65ee-c15a-727e-b3cb-43f791e43ad7" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseNonoperating_019e65ee-c15a-7dbb-8ba4-c3f06de5296d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_InterestExpenseNonoperating_019e65ee-c15a-7dbb-8ba4-c3f06de5296d" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019e65ee-c15a-79b7-a3d9-2fa5de313bd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax_019e65ee-c15a-79b7-a3d9-2fa5de313bd2" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfAcquisitionCosts_019e65ee-c15a-7b11-8f78-6e015d57d0d6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfAcquisitionCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_AmortizationOfAcquisitionCosts_019e65ee-c15a-7b11-8f78-6e015d57d0d6" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_019e65ee-c15a-7c22-afee-45e2691c173e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossOnDispositionOfAssets1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_019e65ee-c15a-7c22-afee-45e2691c173e" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_019e65ee-c15a-75b7-8c1f-1b0a26ff54f2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_SeveranceCosts1_019e65ee-c15a-75b7-8c1f-1b0a26ff54f2" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_GainLossOnRemeasurementOfLiabilityUnderTaxReceivableAgreement_019e65ee-c15a-7be7-9a2b-f1b1293c282a" xlink:href="gpgi-20260630.xsd#gpgi_GainLossOnRemeasurementOfLiabilityUnderTaxReceivableAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_GainLossOnRemeasurementOfLiabilityUnderTaxReceivableAgreement_019e65ee-c15a-7be7-9a2b-f1b1293c282a" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_FairValueInventoryStepUp_019f8590-188d-7b68-bdab-7b169d182875" xlink:href="gpgi-20260630.xsd#gpgi_FairValueInventoryStepUp"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_FairValueInventoryStepUp_019f8590-188d-7b68-bdab-7b169d182875" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019e65ee-c15a-7bb3-a610-698f20d3cbd3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt_019e65ee-c15a-7bb3-a610-698f20d3cbd3" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_MarkToMarketAdjustmentsNet_019e65ee-c15a-71fe-be7b-155bde7c11ff" xlink:href="gpgi-20260630.xsd#gpgi_MarkToMarketAdjustmentsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_MarkToMarketAdjustmentsNet_019e65ee-c15a-71fe-be7b-155bde7c11ff" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_SpinOffCosts_019e65ee-c15a-725d-a11c-804b540478bc" xlink:href="gpgi-20260630.xsd#gpgi_SpinOffCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_gpgi_SpinOffCosts_019e65ee-c15a-725d-a11c-804b540478bc" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e65ee-c15a-7f89-b24e-b7170dca791e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_NetIncomeLoss_019e65ee-c15a-7f89-b24e-b7170dca791e" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019e65ee-c15a-7ebc-92ae-dd53c41206bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_019e65ee-c15a-7ebc-92ae-dd53c41206bd" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e65ee-c15a-7f15-9b78-c9c78735db61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e65ee-c15a-7d52-b268-b9aa10d03816" xlink:to="loc_us-gaap_Assets_019e65ee-c15a-7f15-9b78-c9c78735db61" xlink:type="arc" order="25"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/RELATEDPARTYTRANSACTIONSDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#RELATEDPARTYTRANSACTIONSDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/RELATEDPARTYTRANSACTIONSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionAxis_019fabbd-7a10-7d06-b514-f4fce91cf3a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:to="loc_us-gaap_RelatedPartyTransactionAxis_019fabbd-7a10-7d06-b514-f4fce91cf3a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-7d06-b514-f4fce91cf3a5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_019fabbd-7a10-7d06-b514-f4fce91cf3a5" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-7d06-b514-f4fce91cf3a5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionAxis_019fabbd-7a10-7d06-b514-f4fce91cf3a5" xlink:to="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CompoSecureManagementAgreementMember_019fabbd-7a10-7119-b445-c219db7a843e" xlink:href="gpgi-20260630.xsd#gpgi_CompoSecureManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_CompoSecureManagementAgreementMember_019fabbd-7a10-7119-b445-c219db7a843e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyManagementAgreementMember_019fabbd-7a10-7001-976b-54671e8f3a51" xlink:href="gpgi-20260630.xsd#gpgi_HuskyManagementAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_HuskyManagementAgreementMember_019fabbd-7a10-7001-976b-54671e8f3a51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_BoardAdviserAgreementMember_019fabbe-7113-7586-8509-6280f8018477" xlink:href="gpgi-20260630.xsd#gpgi_BoardAdviserAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_BoardAdviserAgreementMember_019fabbe-7113-7586-8509-6280f8018477" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_PIPEPurchaseAgreementMember_019fabbe-7113-7206-ad5c-68f5ba44e9e8" xlink:href="gpgi-20260630.xsd#gpgi_PIPEPurchaseAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_PIPEPurchaseAgreementMember_019fabbe-7113-7206-ad5c-68f5ba44e9e8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_InvestorRightsAgreementMember_019fabbe-8208-72a4-96bf-21feaf1e0a34" xlink:href="gpgi-20260630.xsd#gpgi_InvestorRightsAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_InvestorRightsAgreementMember_019fabbe-8208-72a4-96bf-21feaf1e0a34" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RegistrationRightsAgreementMember_019fabbe-93c6-7625-8ebe-c1251f71fd81" xlink:href="gpgi-20260630.xsd#gpgi_RegistrationRightsAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionDomain_019fabbd-7a10-75a8-a905-0a56e7db4da7" xlink:to="loc_gpgi_RegistrationRightsAgreementMember_019fabbe-93c6-7625-8ebe-c1251f71fd81" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fabbd-7a10-7eff-8ed7-0988632926d3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:to="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fabbd-7a10-7eff-8ed7-0988632926d3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fabbd-7a10-7eff-8ed7-0988632926d3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fabbd-7a10-7eff-8ed7-0988632926d3" xlink:to="loc_us-gaap_RelatedPartyDomain_019fabbd-7a10-7eff-8ed7-0988632926d3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyDomain_019fabbd-7a10-7e12-8a42-2758b12010ec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_019fabbd-7a10-7eff-8ed7-0988632926d3" xlink:to="loc_us-gaap_RelatedPartyDomain_019fabbd-7a10-7e12-8a42-2758b12010ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RelatedPartyMember_019fabbd-7a10-7734-8e82-d881729c0b8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyDomain_019fabbd-7a10-7e12-8a42-2758b12010ec" xlink:to="loc_us-gaap_RelatedPartyMember_019fabbd-7a10-7734-8e82-d881729c0b8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_CounterpartyNameAxis_019fabbd-7a10-74f8-9879-39085bd5f14e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:to="loc_srt_CounterpartyNameAxis_019fabbd-7a10-74f8-9879-39085bd5f14e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-74f8-9879-39085bd5f14e_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_CounterpartyNameAxis_019fabbd-7a10-74f8-9879-39085bd5f14e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-74f8-9879-39085bd5f14e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-7eec-9cdb-18b648a3c716" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_CounterpartyNameAxis_019fabbd-7a10-74f8-9879-39085bd5f14e" xlink:to="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-7eec-9cdb-18b648a3c716" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_HuskyHoldingsMember_019fabbd-7a10-72a2-af9e-951160a7b924" xlink:href="gpgi-20260630.xsd#gpgi_HuskyHoldingsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-7eec-9cdb-18b648a3c716" xlink:to="loc_gpgi_HuskyHoldingsMember_019fabbd-7a10-72a2-af9e-951160a7b924" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_CompoSecureHoldingsL.L.CMember_019fabbd-a6b9-7778-a88b-a4a70cef8179" xlink:href="gpgi-20260630.xsd#gpgi_CompoSecureHoldingsL.L.CMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain_019fabbd-7a10-7eec-9cdb-18b648a3c716" xlink:to="loc_gpgi_CompoSecureHoldingsL.L.CMember_019fabbd-a6b9-7778-a88b-a4a70cef8179" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019fabbe-7113-776a-974f-d1f9e2890990" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019fabbe-7113-776a-974f-d1f9e2890990" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019fabbe-7113-776a-974f-d1f9e2890990_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019fabbe-7113-776a-974f-d1f9e2890990" xlink:to="loc_us-gaap_ClassOfStockDomain_019fabbe-7113-776a-974f-d1f9e2890990_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019fabbe-7113-790f-aae9-e73f575fc6cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019fabbe-7113-776a-974f-d1f9e2890990" xlink:to="loc_us-gaap_ClassOfStockDomain_019fabbe-7113-790f-aae9-e73f575fc6cf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019fabbe-7113-760a-b2ee-efb8aa453e87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019fabbe-7113-790f-aae9-e73f575fc6cf" xlink:to="loc_us-gaap_CommonClassAMember_019fabbe-7113-760a-b2ee-efb8aa453e87" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019fabbe-8208-7b72-b005-767d3d211d33" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_019e65ee-c15b-7bb8-8319-69f757f18a80" xlink:to="loc_srt_RangeAxis_019fabbe-8208-7b72-b005-767d3d211d33" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fabbe-8208-7b72-b005-767d3d211d33_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019fabbe-8208-7b72-b005-767d3d211d33" xlink:to="loc_srt_RangeMember_019fabbe-8208-7b72-b005-767d3d211d33_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fabbe-8208-78a9-a81f-5a7a6251ae1a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019fabbe-8208-7b72-b005-767d3d211d33" xlink:to="loc_srt_RangeMember_019fabbe-8208-78a9-a81f-5a7a6251ae1a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019fabbe-8208-7261-a942-40ab0fc14f18" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019fabbe-8208-78a9-a81f-5a7a6251ae1a" xlink:to="loc_srt_MaximumMember_019fabbe-8208-7261-a942-40ab0fc14f18" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019fabbe-8208-7d8b-93c8-8bb089890c38" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019fabbe-8208-78a9-a81f-5a7a6251ae1a" xlink:to="loc_srt_MinimumMember_019fabbe-8208-7d8b-93c8-8bb089890c38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementFeePercentage_019fabbd-7a10-77fa-8e77-fc08efdba07d" xlink:href="gpgi-20260630.xsd#gpgi_ManagementFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_ManagementFeePercentage_019fabbd-7a10-77fa-8e77-fc08efdba07d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementAgreementRenewalTerm_019fabbd-7a10-795e-bb0e-7e2dc4226c2f" xlink:href="gpgi-20260630.xsd#gpgi_ManagementAgreementRenewalTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_ManagementAgreementRenewalTerm_019fabbd-7a10-795e-bb0e-7e2dc4226c2f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ManagementFeeExpense_019fabbd-a6b9-7650-ae3e-46162758a378" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ManagementFeeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_us-gaap_ManagementFeeExpense_019fabbd-a6b9-7650-ae3e-46162758a378" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementAgreementExpenses_019fabbd-a6b9-70b1-9d25-74afd3cd4782" xlink:href="gpgi-20260630.xsd#gpgi_ManagementAgreementExpenses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_ManagementAgreementExpenses_019fabbd-a6b9-70b1-9d25-74afd3cd4782" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_ManagementAgreementInitialTerm_019fabbd-a6b9-7c50-bcb5-b06e3a9df6a4" xlink:href="gpgi-20260630.xsd#gpgi_ManagementAgreementInitialTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_ManagementAgreementInitialTerm_019fabbd-a6b9-7c50-bcb5-b06e3a9df6a4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_AnnualCashRetainerFee_019fabbe-7113-7556-8893-845b2301620e" xlink:href="gpgi-20260630.xsd#gpgi_AnnualCashRetainerFee"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_AnnualCashRetainerFee_019fabbe-7113-7556-8893-845b2301620e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_019fabbe-7113-7a24-8d59-912bb5293c61" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_019fabbe-7113-7a24-8d59-912bb5293c61" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionSharePurchased_019fabbe-7113-7999-9b71-2b89bbcfa710" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionSharePurchased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionSharePurchased_019fabbe-7113-7999-9b71-2b89bbcfa710" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionBoardSeatsAboveTenPercent_019fabbe-8208-76f0-b0e7-c57fa50a9c12" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionBoardSeatsAboveTenPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionBoardSeatsAboveTenPercent_019fabbe-8208-76f0-b0e7-c57fa50a9c12" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionOwnershipThresholdPercent_019fabbe-8208-7e56-a476-2ed49535f4b8" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionOwnershipThresholdPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionOwnershipThresholdPercent_019fabbe-8208-7e56-a476-2ed49535f4b8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionBoardSeatsAboveFivePercent_019fabbe-8208-7bdb-8a72-99d845f74243" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionBoardSeatsAboveFivePercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionBoardSeatsAboveFivePercent_019fabbe-8208-7bdb-8a72-99d845f74243" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionLockupPeriod_019fabbe-8208-7587-b436-1f17ea4ba31e" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionLockupPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionLockupPeriod_019fabbe-8208-7587-b436-1f17ea4ba31e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_gpgi_RelatedPartyTransactionDemandRegistrationMeasurementPeriod_019fabbe-93c6-7802-b815-bf0dfcc57516" xlink:href="gpgi-20260630.xsd#gpgi_RelatedPartyTransactionDemandRegistrationMeasurementPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_019fabbd-7a10-7bdb-bc26-a4b2917e78fc" xlink:to="loc_gpgi_RelatedPartyTransactionDemandRegistrationMeasurementPeriod_019fabbe-93c6-7802-b815-bf0dfcc57516" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://gpgi.com/role/SUBSEQUENTEVENTSDetails" xlink:type="simple" xlink:href="gpgi-20260630.xsd#SUBSEQUENTEVENTSDetails"/>
  <link:definitionLink xlink:role="http://gpgi.com/role/SUBSEQUENTEVENTSDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_019e65ee-c15b-7a7f-b2b9-040ccaea6b6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_019e65ee-c15b-7a1d-ab14-c13a40aedccb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e65ee-c15b-7a7f-b2b9-040ccaea6b6c" xlink:to="loc_us-gaap_SubsequentEventTable_019e65ee-c15b-7a1d-ab14-c13a40aedccb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15b-7d91-ba42-297ab6e49379" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019e65ee-c15b-7a1d-ab14-c13a40aedccb" xlink:to="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15b-7d91-ba42-297ab6e49379" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15b-7d91-ba42-297ab6e49379_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15b-7d91-ba42-297ab6e49379" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15b-7d91-ba42-297ab6e49379_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_019e65ee-c15b-78e4-b7a3-12263b636cea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_019e65ee-c15b-7d91-ba42-297ab6e49379" xlink:to="loc_us-gaap_ClassOfStockDomain_019e65ee-c15b-78e4-b7a3-12263b636cea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonClassAMember_019e65ee-c15b-757a-a893-d774fb0d28cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ClassOfStockDomain_019e65ee-c15b-78e4-b7a3-12263b636cea" xlink:to="loc_us-gaap_CommonClassAMember_019e65ee-c15b-757a-a893-d774fb0d28cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019f178c-9224-7bb9-a7e9-656a6d8bd7a3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019e65ee-c15b-7a1d-ab14-c13a40aedccb" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019f178c-9224-7bb9-a7e9-656a6d8bd7a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019f178c-9224-7bb9-a7e9-656a6d8bd7a3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019f178c-9224-7bb9-a7e9-656a6d8bd7a3" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019f178c-9224-7bb9-a7e9-656a6d8bd7a3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019f178c-9224-7fd9-9279-bd9e52c58872" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019f178c-9224-7bb9-a7e9-656a6d8bd7a3" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019f178c-9224-7fd9-9279-bd9e52c58872" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019f178c-a4d0-7b53-84dc-ac54e383b809" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_019f178c-9224-7fd9-9279-bd9e52c58872" xlink:to="loc_us-gaap_SubsequentEventMember_019f178c-a4d0-7b53-84dc-ac54e383b809" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsPayableAmountPerShare_019e65ee-c15b-71bc-93f4-5e1b157afdec" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsPayableAmountPerShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e65ee-c15b-7a7f-b2b9-040ccaea6b6c" xlink:to="loc_us-gaap_DividendsPayableAmountPerShare_019e65ee-c15b-71bc-93f4-5e1b157afdec" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DividendsCommonStockStock_019e65ee-c15b-7c18-9647-5dbd0159ba04" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DividendsCommonStockStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e65ee-c15b-7a7f-b2b9-040ccaea6b6c" xlink:to="loc_us-gaap_DividendsCommonStockStock_019e65ee-c15b-7c18-9647-5dbd0159ba04" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
