[Python] Mypy fails with overloads and literals

I'm trying to understand typing.overload and have applied it in a simple case where I want a function that takes input x: Literal["foo", "bar"] and returns the list [x].

I'd like mypy to type the resulting list as list[Literal["foo"]] or list[Literal["bar"]] depending on the value of x.

I know I could achieve this with a TypeVar, but I'd still like to understand why the code below fails with the following error:

test.py:14: error: Overloaded function implementation cannot produce return type of signature 1
test.py:14: error: Overloaded function implementation cannot produce return type of signature 2


from typing import Literal, overload


@overload
def f(x: Literal["foo"]) -> list[Literal["foo"]]:
...


@overload
def f(x: Literal["bar"]) -> list[Literal["bar"]]:
...


def f(x: Literal["foo", "bar"]) -> list[Literal["foo", "bar"]]:
return [x]

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