Manimgl does not find the imports.

Hi guys
I need your help. I have cloned the repo to rebuild the videos. Unfortunately I have several problems.
In various instructions I was told to copy the file to be executed to the root directory of the git. I have done that. After that I started the Python file with Manim. It came to an error message, this can be seen in the picture. It means that it cannot find the file ``manim_imports_ext``. This is demonstrably there.
Can you help me to solve the problem?

Thanks in advance.