inherit-non-class / E0239#

Message emitted:

Inheriting %r, which is not a class.

Description:

Used when a class inherits from something which is not a class.

Correct code:

class Fruit:
    def __bool__(self):
        pass

Problematic code:

class Fruit(bool):  # [inherit-non-class]
    pass

Created by the classes checker.