Mopidy fails with PyGObject

Since today I can’t start mopidy on my mac anymore (don’t exactly know what I changed since yesterday).
It says "ImportError: cannot import name _gi".
I already googled and tried every possible solution for 3h or so.
So I am quite desperate, and hope you are so kind and can help!

When I use brew to re-install mopidy it fails with:
Mopidy install fails on gst-python@2 dependency https://github.com/mopidy/homebrew-mopidy/issues/35
I tried to install gst-python@2 using brew install gst-python --with-python2 but this fails with Error: invalid option: --with-python2
I also tried to install pygobject which also fails.
Working: python3 --> import gi
Doesn’t work: python --> import gi --> cannot import name _gi

I also manually copied the gi folder from python3.7/site-packages to python2.7/site-packages. But it doesn’t help :frowning: