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   <link:roleRef xlink:type="simple" xlink:href="213800DHCALLH8IRJV57-2021-12-31.xsd#id_181" roleURI="https://www.mearsgroup.co.uk/xbrl/role/all/ias_7_role-520000"/>
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentProvisionsForEmployeeBenefits" xlink:label="ifrs-full_NoncurrentProvisionsForEmployeeBenefits" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
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                            order="28.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherLongtermProvisions" xlink:label="ifrs-full_OtherLongtermProvisions" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
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                            weight="1.0"
                            order="29.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxLiabilities" xlink:label="ifrs-full_DeferredTaxLiabilities" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_DeferredTaxLiabilities"
                            order="30.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentFinancialLiabilities" xlink:label="ifrs-full_OtherNoncurrentFinancialLiabilities" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_OtherNoncurrentFinancialLiabilities"
                            order="50.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_LongtermBorrowings" xlink:label="ifrs-full_LongtermBorrowings" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_LongtermBorrowings"
                            weight="1.0"
                            order="51.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLeaseLiabilities" xlink:label="ifrs-full_NoncurrentLeaseLiabilities" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_NoncurrentLeaseLiabilities"
                            weight="1.0"
                            order="52.0"
                          xlink:type="arc"/>
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   <link:calculationLink xlink:role="https://www.mearsgroup.co.uk/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Assets" xlink:label="ifrs-full_Assets" xlink:type="locator"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets" xlink:label="ifrs-full_NoncurrentAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_NoncurrentAssets"
                            order="10.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentAssets" xlink:label="ifrs-full_CurrentAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_CurrentAssets"
                            order="20.0"
                            weight="1.0"
                          xlink:type="arc"/>
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   <link:calculationLink xlink:role="https://www.mearsgroup.co.uk/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets" xlink:label="ifrs-full_NoncurrentAssets" xlink:type="locator"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PropertyPlantAndEquipment" xlink:label="ifrs-full_PropertyPlantAndEquipment" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_PropertyPlantAndEquipment"
                            order="10.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Goodwill" xlink:label="ifrs-full_Goodwill" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_Goodwill"
                            order="30.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IntangibleAssetsOtherThanGoodwill" xlink:label="ifrs-full_IntangibleAssetsOtherThanGoodwill" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_IntangibleAssetsOtherThanGoodwill"
                            order="40.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_InvestmentsInSubsidiariesJointVenturesAndAssociates" xlink:label="ifrs-full_InvestmentsInSubsidiariesJointVenturesAndAssociates" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_InvestmentsInSubsidiariesJointVenturesAndAssociates"
                            order="60.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxAssets" xlink:label="ifrs-full_DeferredTaxAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_DeferredTaxAssets"
                            order="100.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentFinancialAssets" xlink:label="ifrs-full_OtherNoncurrentFinancialAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_OtherNoncurrentFinancialAssets"
                            order="120.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ContingentConsiderationRecognisedAsOfAcquisitionDate" xlink:label="ifrs-full_ContingentConsiderationRecognisedAsOfAcquisitionDate" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_ContingentConsiderationRecognisedAsOfAcquisitionDate"
                            weight="-1.0"
                            order="121.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RecognisedAssetsDefinedBenefitPlan" xlink:label="ifrs-full_RecognisedAssetsDefinedBenefitPlan" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentAssets"
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                            order="122.0"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_ReimbursementRightsAtFairValue" xlink:label="ifrs-full_ReimbursementRightsAtFairValue" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_ReimbursementRightsAtFairValue"
                            weight="1.0"
                            order="123.0"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RightofuseAssets" xlink:label="ifrs-full_RightofuseAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_RightofuseAssets"
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                            order="124.0"
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                          xlink:from="ifrs-full_CurrentAssets"
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_TradeAndOtherCurrentReceivables"
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_CurrentTaxAssetsCurrent"
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_CashAndCashEquivalents"
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                          xlink:to="ifrs-full_Equity"
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                          xlink:to="ifrs-full_Liabilities"
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