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  <xs:element id="iiiv_TaxReceivableAgreementPercentOfTaxBenefitsPayableToContinuingEquityOwners" abstract="false" name="TaxReceivableAgreementPercentOfTaxBenefitsPayableToContinuingEquityOwners" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
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  <xs:element id="iiiv_ExpectedPaymentsForRepurchaseOfRedeemableNoncontrollingInterest" abstract="false" name="ExpectedPaymentsForRepurchaseOfRedeemableNoncontrollingInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="iiiv_PeriodOfPaymentToContinuingEquityOwners" abstract="false" name="PeriodOfPaymentToContinuingEquityOwners" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="iiiv_LesseeFinanceLeaseNumberOfContracts" abstract="false" name="LesseeFinanceLeaseNumberOfContracts" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="iiiv_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="iiiv_DisposalGroupIncludingDiscontinuedOperationAccruedContingentConsiderationLongTermAssetsHeldForSale" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationAccruedContingentConsiderationLongTermAssetsHeldForSale" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="iiiv_DisposalGroupIncludingDiscontinuedOperationAccruedContingentConsideration" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationAccruedContingentConsideration" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="iiiv_AccruedExpensesAndOtherCurrentLiabilitiesMember" abstract="true" name="AccruedExpensesAndOtherCurrentLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="iiiv_A2020EquityIncentiveAwardPlanMember" abstract="true" name="A2020EquityIncentiveAwardPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="iiiv_NoncontrollingInterestIncreaseFromRecapitalizationOfContribution" abstract="false" name="NoncontrollingInterestIncreaseFromRecapitalizationOfContribution" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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</xs:schema>
