Literal and Enum types with generic function

[sylee957]

Given the types:

from enum import Enum
from typing import Literal, NewType, TypeVar

T = TypeVar("T")


def identity(x: T) -> T:
    return x

Two = NewType("Two", int)


class Num(Enum):
    TWO = 2

Literal and Enum fails to type check

def test(x: Literal[2]) -> Literal[2]:
    return identity(identity(x))

def test(x: Literal[Num.TWO]) -> Literal[Num.TWO]:
    return identity(identity(x))

because of some unnecessary widening of types for generics.

While the only function that passes the type check is NewType

def test(x: Two) -> Two:
    return identity(identity(x))