Extremely slow work of puthon-based applications

After upgrating to 12.1 Thumbleweed, python-based applications work extremely slow. The slowest is EasyTAG. It takes about 10-20 times more time than on 11.4.
I remember such bug when 11.4 had just released, then it was fixed and I remember announcement about the fix. But I don’t remember where it was.
Does anyone remember, or know how to fix it? It’s really really annoying. Or at least please confirm the problem.
Thanks!