kam193 added the comment:
@Jonas: I know, running those tests isn't so easy, I think a few libraries are
incompatible with python 3.9/3.10 yet or I didn't find right prerequisites. But
fortunately, everything is running on patched 3.8, so after back-porting I c
kam193 added the comment:
@Stefan: Today I run unit tests for Flask-SQLAlchemy (v2.4.3) as well as for
aioxmpp (another library reported this problem
https://github.com/horazont/aioxmpp/issues/342). In both cases patch is
successful: tests fail on Python 3.8.4 but pass on patched Python
New submission from kam193 :
CPython 3.8.4 broke previously correct custom __setattr__ implementation, when
metaclass inheritances from multiple classes, including not-meta.
Following code:
```
class Meta(type):
def __setattr__(cls, key, value):
type.__setattr__(cls, key, value
