[Python] How can one get multiple inheritance working when there are arguments? [duplicate]

Can somebody explain me, how to handle initializer arguments with python's super() keyword? I am frustrated. There are already many posts discussing __init__ and MRO with the conclusion to always call super().__init__ in every initializer. The examples typically come without any additional arguments. However, super() seems to be completely broken for multiple inheritance as soon as there are arguments to __init__.

Simple example of multiple inheritance with an (unused) argument:

class A(object):
def __init__(self, arg):
print("A")

class B(object):
def __init__(self, arg):
print("B")

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

A(1) # -> A
B(1) # -> B
C(1) # -> C A (B.__init__ is never called)


The intuitive way does not work with the way super() is designed:

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

C(1) # -> C A A (A.__init__ is called twice because MRO is reset)


So, the problem is, that class A does not call super. But:

class A(object):
def __init__(self, arg):
print("A")
super().__init__(arg)

A(1) # -> TypeError because it calls object.__init__ with one argument
C(1) # -> C A B


so, now I cannot instantiate A anymore. But this fails too:

class A(object):
def __init__(self, arg):
print("A")
super().__init__()

C(1) # -> TypeError because it calls B.__init__ without argument


So the problem is, that the super() call in the simple class A might either go to object (which supports only zero arguments) or to the class B (which requires one argument). The problem arises as soon as there are arguments to the initializers and I see no solution.

Do you know any solution to this problem? How do you handle super()? It seems to me, that super() should be avoided for any practical example of __init__. It feels unsatisfying to see a flawed language feature and no warnings about using it.

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