mixin.py

class Item:
    def print(self):
        print(self.getText())
    
    def getText(self):
        return "foo"

class SpecialItem:
    def print(self):
        print("SpecialItem: " + self.getText())

class WithText(Item):
    def getText(self):
        return "custom text"

class MyItem(SpecialItem, WithText):
    pass

item = MyItem()
item.print()