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      <link:calculationArc
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                          xlink:to="ifrs-full_OtherLongtermProvisions"
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                          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_NoncurrentPayables" xlink:label="ifrs-full_NoncurrentPayables" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
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                          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_NoncurrentProvisionsForEmployeeBenefits" xlink:label="ifrs-full_NoncurrentProvisionsForEmployeeBenefits" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
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   <link:calculationLink xlink:role="https://www.immsi.it/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
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      <link:calculationArc
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                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_CurrentAssets"
                            weight="1.0"
                            order="1"
                          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_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"
                            weight="1.0"
                            order="2"
                          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_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners" xlink:label="ifrs-full_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleOrAsHeldForDistributionToOwners"
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                            order="3"
                          xlink:type="arc"/>
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   <link:calculationLink xlink:role="https://www.immsi.it/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
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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_PropertyPlantAndEquipment" xlink:label="ifrs-full_PropertyPlantAndEquipment" xlink:type="locator"/>
      <link:calculationArc
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                          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_InvestmentProperty" xlink:label="ifrs-full_InvestmentProperty" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_InvestmentProperty"
                            order="20.0"
                            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
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          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_NoncurrentReceivables" xlink:label="ifrs-full_NoncurrentReceivables" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_NoncurrentReceivables"
                            order="80.0"
                            weight="1.0"
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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_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_CurrentTaxAssetsNoncurrent" xlink:label="ifrs-full_CurrentTaxAssetsNoncurrent" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_CurrentTaxAssetsNoncurrent"
                            order="110.0"
                            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_IntangibleAssetsAndGoodwill" xlink:label="ifrs-full_IntangibleAssetsAndGoodwill" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_IntangibleAssetsAndGoodwill"
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                            order="121.0"
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      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_Inventories"
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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_TradeAndOtherCurrentReceivables" xlink:label="ifrs-full_TradeAndOtherCurrentReceivables" xlink:type="locator"/>
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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:to="ifrs-full_OtherCurrentFinancialAssets"
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                          xlink:from="ifrs-full_CurrentAssets"
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                          xlink:to="ifrs-full_Equity"
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                          xlink:to="ifrs-full_NoncontrollingInterests"
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                          xlink:from="ifrs-full_CurrentLiabilities"
                          xlink:to="ifrs-full_OtherShorttermProvisions"
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                          xlink:to="ifrs-full_OtherCurrentPayables"
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