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  <xsd:element name="EmployeeBenefitPlanNoteReceivableFromParticipantTerm" id="osbc_EmployeeBenefitPlanNoteReceivableFromParticipantTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear1Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear2Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear2Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear3Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear3Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear4Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear4Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear5Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear5Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NumberOfYearsOfVestingServiceCompletedUptoYear6Member" id="osbc_NumberOfYearsOfVestingServiceCompletedUptoYear6Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ScheduleOfProfitSharingContributionsTableTextBlock" id="osbc_ScheduleOfProfitSharingContributionsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
