[Python] Generic[T] class with access to type parameter of classmethod in Python 3.12

Similar to how one could retrieve a type from a generic class type signature via a class method, I am now interested in doing the same for the class method's type signature itself.

For example, I would like to print the concrete type of T in this example:

class MyClass[T]:
kind: type[T]

@classmethod
def make_class[T](cls) -> "MyClass[T]":
instance = cls()
instance.kind = ...
print(instance.kind)
return instance


Currently this would result in an exception:

>>> MyClass.make_class[int]()
TypeError: 'method' object is not subscriptable


A custom "classmethod" decorator would be ideal as I imagine it would require the least amount of "hacking" to the way generic classes work.

class MyClass[T]:
kind: type[T]

@typed_classmethod
def make_class[T](cls) -> "MyClass[T]":
...

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