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From Python3's documentation super() "returns a proxy object that delegates method calls to a parent or sibling class of type." What does that mean?

Suppose I have the following code:

class SuperClass():
    def __init__(self):
        print("__init__ from SuperClass.")
        print("self object id from SuperClass: " + str(id(self)))

class SubClass(SuperClass):
    def __init__(self):
        print("__init__ from SubClass.")
        print("self object id from SubClass: " + str(id(self)))
        super().__init__()


sc = SubClass()

The output I get from this is:

__init__ from SubClass. self object id from SubClass: 140690611849200 __init__ from SuperClass. self object id from SuperClass: 140690611849200

This means that in the line super().__init__(), super() is returning the current object which is then implicitly passed to the superclass' __init__() method. Is this accurate or am I missing something here?

To put it simply, I want to understand the following:

When super().__init__() is run,

1. What exactly is being passed to __init__() and how? We are calling it on super() so whatever this is returning should be getting passed to the __init__() method from what I understand about Python so far.
2. Why don't we have to pass in self to super().__init__()?

Answers

returns a proxy object that delegates method calls to a parent or sibling class of type.

This proxy is an object that acts as the method-calling portion of the parent class. It is not the class itself; rather, it's just enough information so that you can use it to call the parent class methods.

If you call __init__(), you get your own, local, sub-class __init__ function. When you call super(), you get that proxy object, which will redirect you to the parent-class methods. Thus, when you call super().__init__(), that proxy redirects the call to the parent-class __init__ method.

Similarly, if you were to call super().foo, you would get the foo method from the parent class -- again, re-routed by that proxy.

Is that clear to you?

Responses to OP comments

But that must mean that this proxy object is being passed to __init__() when running super().__init__() right?

Wrong. The proxy object is like a package name, such as calling math.sqrt(). You're not passing math to sqrt, you're using it to denote which sqrt you're using. If you wanted to pass the proxy to __init__, the call would be __init__(super()). That call would be semantically ridiculous, of course.

When we have to actually pass in self which is the sc object in my example.

No, you are not passing in sc; that is the result of the object creation call (internal method __new__), which includes an invocation of init. For __init__, the self object is a new item created for you by the Python run-time system. For most class methods, that first argument (called self out of convention, this in other languages) is the object that invoked the method.