At my organization we use a release of VS2017 that does not include the 7.3 version of the C# compiler and cannot update because we are fixed to a specific C++ ABI. I am trying to use VS2019 to build and deploy pythonnet using some tips I found here but hit this issue when building clrmodule.15:

Error MSB4062 The "RGiesecke.DllExport.MSBuild.DllExportAppDomainIsolatedTask" task could not be loaded from the assembly C:\Users\mkoubaa\.nuget\packages\unmanagedexports\1.2.7\tools\RGiesecke.DllExport.MSBuild.dll. Could not load file or assembly 'Microsoft.Build.Utilities, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified. Confirm that the <UsingTask> declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask. clrmodule.15 C:\Users\mkoubaa\.nuget\packages\unmanagedexports\1.2.7\tools\RGiesecke.DllExport.targets 58

Has anyone got this to work and if so what did you do? A better question might be how UnmanagedExports is making use of Microsoft.Build.Utilities. I know that there is a modernization project that may address this in the future.