One thing not mentioned by anyone yet, that kinda annoys me is the fact that Python libraries use different naming conventions. Even though PEP 8 has existed for 17 years now, there are many examples where I see lower_case_with_underscores mixed with lowercase and camelCase in the function names.

I know that many libraries and Python standard lib itself predate this PEP but I don't understand why Python 3, which broke backward compatibility anyways, did not fix that at least in the standard library.