pythonnet: cannot find class in module

Environment

• Pythonnet version:3.0.0
• Python version:3.8.3
• Operating System:windows10
• .NET Runtime:dotnet core 5.0

Details

• get error:

Traceback (most recent call last):
  File ".\test.py", line 15, in <module>
    from MyApp  import Class1
ImportError: cannot import name 'Class1' from 'MyApp' (unknown location)

• my config file:

{
  "runtimeOptions": {
    "tfm": "netcoreapp5.0",
    "framework": {
      "name": "Microsoft.NETCore.App",
      "version": "5.0.2"
    }
  }
}

• python code

    from clr_loader import get_coreclr
    from pythonnet import set_runtime
    
    rt = get_coreclr("D:\\test\\BotTest\\test.runtimeconfig.json")
    set_runtime(rt)
    
    import clr
    import sys
    import System
    sys.path.append("D:\\test\\BotTest\\MyApp\\bin\\Debug\\net5.0")
    clr.FindAssembly("MyApp")
    
    clr.AddReference("MyApp")
    from System  import Console
    from MyApp  import Class1

• c# code

using System;

namespace MyApp
{
    public class Class1
    {
        public static void f(){
            Console.WriteLine("zzz");
        }
    }
}

• It seems that latest version does not work well for dotnet core