Python Mixin - Unresolved Attribute Reference [PyCharm]

Question

I am using a mixin to separate a range of functionality to a different class. This Mixin is only supposed to be mixable with the only child class:

class Mixi         


        

Answer 1

Declare the necessary fields in the Mixin like:

class Mixin:
    foo:str

    def complex_operation(self):
        return self.foo.capitalize() 

This way the mixin actually declares the fields a class must have to be able to use this mixin. Type hint will create warnings if extending class will put incompatible type into declared field.

edit: Replaced foo = None with foo:str as suggested by @valex