all_interval.csproj

<Project Sdk="Microsoft.NET.Sdk">
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    <RollForward>LatestMajor</RollForward>
    <RestoreSources>../../packages;$(RestoreSources);https://api.nuget.org/v3/index.json</RestoreSources>
    <AssemblyName>Google.OrTools.all_interval</AssemblyName>
    <IsPackable>true</IsPackable>
  </PropertyGroup>

  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugType>full</DebugType>
    <Optimize>true</Optimize>
    <GenerateTailCalls>true</GenerateTailCalls>
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  <ItemGroup>
    <Compile Include="all_interval.cs" />
    <PackageReference Include="Google.OrTools" Version="9.0.*" />
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</Project>