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main.py

from typing import Generic, TypeVar, cast, reveal_type

T = TypeVar("T")

class Foo(Generic[T]): 
    def __init__(self, t: T):
        self.t = t
    
    def print(self, t: T): 
        print(t, self.t)

class Foo2(Foo[T], Generic[T]): 
    def print(self, t: T):
        if t == self.t: 
            print("equal")
        else: 
            Foo.print(self, t)

def test(check_equal: bool) -> None:
    a = (Foo2 if check_equal else Foo)(3)
    reveal_type(a)
    a.print(4)
    a.print("not int")

    printer = Foo2 if check_equal else Foo
    reveal_type(printer)
    p = printer(3)
    reveal_type(p)
    p.print(4)
    p.print("not int")

    p = cast("type[Foo[int]]", printer)(3)
    reveal_type(p)
    p.print(4)
    p.print("not int")