Python super() in nested multiple-inheritance

Question

I recently had a problem understanding the code below：

class A(object):
    def __init__(self):
        print("go A go!")

class B(A):
    def __init__(self):
        super(B, self).__init__()
        print("go B go!")

class C(A):
    def __init__(self):
        super(C, self).__init__()
        print("go C go!")


class D(B,C):
    def __init__(self):
        super(D, self).__init__()
        print("go D go!")
d = D()

The result I got is:

go A go!
go C go!
go B go!
go D go!

I understand the use of super() in simple multiple-inheritance but I really don't know how it got this result.

Answer 1

Python uses C3 linearlization to define the order (Method Resolution Order ). It produced the following order:

D.__mro__
(__main__.D, __main__.B, __main__.C, __main__.A, builtins.object)

Since you are calling the super first and the printing, it results the printing in reverse order (similar to call order in recursion)