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  <xs:element id="atk_SOFRLoanMember" abstract="true" name="SOFRLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_Leaseliability" abstract="false" name="Leaseliability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_SixMonthSecuredOvernightFinancingRateSOFRMember" abstract="true" name="SixMonthSecuredOvernightFinancingRateSOFRMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_FinancingCashFlowsFromFinanceLeases" abstract="false" name="FinancingCashFlowsFromFinanceLeases" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_BrandDomain" abstract="true" name="BrandDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_LineOfCreditFacilityInterestRateFloor" abstract="false" name="LineOfCreditFacilityInterestRateFloor" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="atk_DilutedEarningsPerShareNumeratorAbstract" abstract="true" name="DilutedEarningsPerShareNumeratorAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="atk_AtkinsDomain" abstract="true" name="AtkinsDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_BrandAxis" abstract="true" name="BrandAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="atk_PrivateWarrantsMember" abstract="true" name="PrivateWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_Financeleasecost" abstract="false" name="Financeleasecost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_DocumentInformationAbstract" abstract="true" name="DocumentInformationAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="atk_EarningsPerShareNumeratorAbstract" abstract="true" name="EarningsPerShareNumeratorAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="atk_WarrantLiabilities" abstract="false" name="WarrantLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_NumeratorForDilutedEarnings" abstract="false" name="NumeratorForDilutedEarnings" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_NonCashProceedsFromSaleOfBusiness" abstract="false" name="NonCashProceedsFromSaleOfBusiness" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_ScheduleofWeightedAverageRemainingLeaseTermsTableTextBlock" abstract="false" name="ScheduleofWeightedAverageRemainingLeaseTermsTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="atk_ScheduleofSupplementalCashFlowInformationRelatedtoLeasesTableTextBlock" abstract="false" name="ScheduleofSupplementalCashFlowInformationRelatedtoLeasesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="atk_EarningsPerShareDenominatorAbstract" abstract="true" name="EarningsPerShareDenominatorAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="atk_EffectiveIncomeTaxRateReconciliationIncreaseDecreaseFromPriorYearPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationIncreaseDecreaseFromPriorYearPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="atk_LineOfCreditCovenantComplianceCreditExtensionPercentOfAvailableCommitments" abstract="false" name="LineOfCreditCovenantComplianceCreditExtensionPercentOfAvailableCommitments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="atk_DilutiveAdjustmentAxis" abstract="true" name="DilutiveAdjustmentAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="atk_DilutiveAdjustmentDomain" abstract="true" name="DilutiveAdjustmentDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_OperatingleaserightofuseassetsrecognizedafterASU201602transition" abstract="false" name="OperatingleaserightofuseassetsrecognizedafterASU201602transition" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_WarrantsOutstandingPerWarrantFairValue" abstract="false" name="WarrantsOutstandingPerWarrantFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_LeaseassetsandliabilitiesTableTextBlock" abstract="false" name="LeaseassetsandliabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="atk_Leaserightofuseasset" abstract="false" name="Leaserightofuseasset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_OperatingLeaseImpairmentLossNetOfGainLossOnTerminationOfLease" abstract="false" name="OperatingLeaseImpairmentLossNetOfGainLossOnTerminationOfLease" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_IncrementalCommonSharesAttributabletoDilutiveEffectofStockOptions" abstract="false" name="IncrementalCommonSharesAttributabletoDilutiveEffectofStockOptions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="atk_LesseeOperatingLeaseLeaseNotYetCommencedExpectedPayments" abstract="false" name="LesseeOperatingLeaseLeaseNotYetCommencedExpectedPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="atk_FinanceleasesMember" abstract="true" name="FinanceleasesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_SecuredOvernightFinancingRateSOFRMember" abstract="true" name="SecuredOvernightFinancingRateSOFRMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_DilutedEarningsPerShareDenominatorAbstract" abstract="true" name="DilutedEarningsPerShareDenominatorAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="atk_OneMonthSecuredOvernightFinancingRateSOFRMember" abstract="true" name="OneMonthSecuredOvernightFinancingRateSOFRMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_QuestMember" abstract="true" name="QuestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_LineOfCreditCovenantCompliancePostReductionNetLeverageRatio" abstract="false" name="LineOfCreditCovenantCompliancePostReductionNetLeverageRatio" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="atk_ThreeMonthSecuredOvernightFinancingRateSOFRMember" abstract="true" name="ThreeMonthSecuredOvernightFinancingRateSOFRMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_IntangibleassetsinprogressMember" abstract="true" name="IntangibleassetsinprogressMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_BarclaysBankPLCAndOtherPartiesMember" abstract="true" name="BarclaysBankPLCAndOtherPartiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="atk_InternationalMember" abstract="true" name="InternationalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
</xs:schema>
