Difference between __getattr__ vs __getattribute__

Question

I am trying to understand when to use __getattr__ or __getattribute__. The documentation mentions __getattribute__ applies to new-sty

Answer 1

I find that no one mentions this difference:

__getattribute__ has a default implementation, but __getattr__ does not.

class A:
    pass
a = A()
a.__getattr__ # error
a.__getattribute__ # return a method-wrapper

This has a clear meaning: since __getattribute__ has a default implementation, while __getattr__ not, clearly python encourages users to implement __getattr__.