No way to call .net core 6.0 dll from python

Environment

• Pythonnet version: 3.0.1
• Python version: 3.11.0
• Operating System: Debian GNU/Linux 11 (bullseye)
• .NET Runtime: .net core 6.0

Details

Goal: attempt to call a simple static function in a .net core dll from a python script

The C# project contains only one file:

namespace Math
{
	public class Calculator
	{
		public static int Factorial(int number)
		{
			int i;
			int fact = 1;
			for (i = 1; i <= number; i++)
			{
				fact *= i;
			}
			return fact;
		}
	}
}

The python script is the following:

from pythonnet import load

load("coreclr")
import clr

reference = clr.AddReference('./Math/bin/Debug/net6.0/publish/Math')
print(reference)
from Math import Calculator

factorial = Calculator.Factorial(6)
print(factorial)

• If there was a crash, please include the traceback here.

# python factorial.py 
Math, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null
Traceback (most recent call last):
  File "factorial.py", line 8, in <module>
    from Math import Calculator
ImportError: cannot import name 'Calculator' from 'Math' (unknown location)

To reproduce the environment, here’s a dockerfile:

FROM python:3.11.0-slim-bullseye
    
# Install .Net	
RUN apt-get update
RUN apt-get -y install wget

RUN wget https://packages.microsoft.com/config/debian/11/packages-microsoft-prod.deb -O packages-microsoft-prod.deb
RUN dpkg -i packages-microsoft-prod.deb
RUN rm packages-microsoft-prod.deb

RUN apt-get update && \
    apt-get install -y dotnet-sdk-6.0

RUN pip install pythonnet

ENV DOTNET_SYSTEM_GLOBALIZATION_INVARIANT=1

[filmor]

The issue is that you have a Math sub folder in the directory that you run factorial.py from. Python’s namespace package loader will take precedence over ours and the respective namespace package is of course empty. Rename the Math directory to something else and it will work:

[0x78f1935]

I hate name collisions 😅 , thanks for saving me a headache!