子类方法在Python中调用父类的普通方法

Question

Consider the following snippet in Python:

class A:
    def f(self, arg):
        print(self, arg)

class B(A):
    @classmethod
    def f(cls, arg):
        super(B, cls).f(arg)
        print(cls, arg)

B.f(1)

I know it's wrong to write like this, but I'm trying to understand what's going on behind the scenes. Why do I need to pass the first argument explicitly in call to inherited function? If this snippet is run, I get an exception that the required positional argument was not provided.

When I call Bf(1) , the first argument (the class B ) is passed implicitly. I thought the same should be the case when I call the inherited ordinary method through class instance: self should be class B .

Is it some interpreter magic - say, it looks at class A , sees that f is ordinary function there, and does not set the first argument implicitly because it's called as class method?

Answer 1

I ran the code successfully by simply changing

super (B, cls).f(arg)

to:

super (B, cls).f (cls, arg)

and it worked fine. I guess the class isn't passed implicitly.