Усі секрети Классметоду / Python classmethod internals

class MyBoundClassMethod:

    def __init__(self, func, cls):
        self.func = func
        self.cls = cls

    def __call__(self, *args, **kwargs):
        return self.func(self.cls, *args, **kwargs)


class MyClassMethod:

    def __init__(self, func):
        self.func = func

    def __get__(self, instance, owner):
        return MyBoundClassMethod(self.func, owner)


class MyClass:

    @classmethod
    def print_message(cls, msg):
        print(f"id {id(cls)}, self {cls}, '{msg}'")

    @MyClassMethod
    def print_message_2(cls, msg):
        print(f"id {id(cls)}, self {cls}, '{msg}'")


MyClass.print_message("Hi there")
MyClass.print_message_2("Hi there")

my_obj = MyClass()
my_obj.print_message("Hi there")
my_obj.print_message_2("Hi there")