Inherit multiple methods with same name from multiple classes

I have two parent classes that share method names. I’d like to subclass them and reassign their methods under different names to the subclass. This is made complicated because these methods use other methods with shared names as well. Contrived but minimal example:

class Foo1():
    def __init__(self):
        super().__init__()

    def print(self):
        print(self.get())

    def get(self):
        return 1


class Foo2():
    def __init__(self):
        super().__init__()

    def print(self):
        print(self.get())

    def get(self):
        return 2


class Foo(Foo1, Foo2):
    def __init__(self):
        super().__init__()

        self.print1 = super().print
        self.print2 = super(Foo1, self).print


foo = Foo()
foo.print1()
>>> 1
foo.print2()
>>> 1

In the example above, foo.print1() prints 1 as expected, but foo.print2() prints 1 instead of 2. I would like to structure Foo such that it calls Foo2’s print and get methods and thus prints 2.

I understand this is because the name “self” actually points to Foo(), and so the methods “print” and “get” are pointing to Foo1’s methods due to Foo1 being first in the MRO.

For my use case, it doesn’t even make sense for Foo() to have “print” and “get” methods, only “print1” and “print2”. This makes me suspect that I’m going about it all wrong. Is there a better way to construct a subclass that correctly inherits these methods from Foo1 and Foo2?

Answer

Have your class wrap Foo1 and Foo2 instances rather than using multiple inheritance.

class Foo:
    def __init__(self):
        foo1 = Foo1()
        foo2 = Foo2()

        self.print1 = foo1.print
        self.print2 = foo2.print

        self.get1 = foo1.get
        self.get2 = foo2.get

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Answer