How to use `super` in multiple inheritance?

Question

Let suppose we have defined two classes:

class A():
    def __init__(self):
        self.a = 0

class B():
    def __init__(self):
        self.b = 0

Now, we want to define a third class C that inherits from A and B:

class C(A, B):
    def __init__(self):
        A.__init__(self)   # how to do this using super()
        B.__init__(self)   # how to do this using super()

Answer 1

You did not specify whether you are Python 2 or Python 3 and it matters as we shall see. But either way, if you will be using super() in a derived class to initialize the base classes, then the base classes must use super() also. So,

For Python 3:

class A():
    def __init__(self):
        super().__init__()
        self.a = 0

class B():
    def __init__(self):
        super().__init__()
        self.b = 0

class C(A, B):
    def __init__(self):
        super().__init__()

For Python 2 (where classes must be new-style classes) or Python 3

class A(object):
    def __init__(self):
        super(A, self).__init__()
        self.a = 0

class B(object):
    def __init__(self):
        super(B, self).__init__()
        self.b = 0

class C(A, B):
    def __init__(self):
        super(C, self).__init__()