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        <link:definition>0001 - Document - Cover</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.invesco.com/role/FeeTable" id="FeeTable">
        <link:definition>0002 - Disclosure - Summary of Fees &amp; Expenses And Example Table</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.invesco.com/role/FinancialHighlights" id="FinancialHighlights">
        <link:definition>0003 - Disclosure - Senior Securities</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.invesco.com/role/GeneralDescriptionOfRegistrant" id="GeneralDescriptionOfRegistrant">
        <link:definition>0004 - Disclosure - General Description of Registrant</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>0005 - Disclosure - Capital Stock Long Term Debt And Other Securities</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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  <element name="EnvironmentalSocialAndGovernanceConsiderationsRiskMember" id="ck0000853180_EnvironmentalSocialAndGovernanceConsiderationsRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" nillable="true"/>
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  <element name="HighYieldDebtSecuritiesJunkBondRiskMember" id="ck0000853180_HighYieldDebtSecuritiesJunkBondRiskMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" nillable="true"/>
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