ParamSpec seems to get lost with partial() #18589

from functools import partial
from typing import Any, Callable, Coroutine, Generic, ParamSpec, TypeVar

_R = TypeVar("_R")
_P = ParamSpec("_P")

class Wrapper(Generic[_P, _R]):
    def __init__(self, fn: Callable[_P, Coroutine[Any, Any, _R]]) -> None:
        self.fn = fn

    async def __call__(self, *args: _P.args, **kwargs: _P.kwargs) -> _R:
        return await self.fn(*args, **kwargs)

async def coro(val: int) -> int:
    return val

async def test() -> None:
    coro_wrapped = Wrapper(coro)
    reveal_type(coro_wrapped)  # Revealed type is "Wrapper[[val: builtins.int], builtins.int]"
    await coro_wrapped(3, 2)  # error: Too many arguments for "__call__" of "Wrapper"  [call-arg]

    partial_wrapped = Wrapper(partial(coro, 2))
    reveal_type(partial_wrapped)  # Revealed type is "Wrapper[[*args: Any, **kwargs: Any], builtins.int]"
    await partial_wrapped(4)  # XXX: Should be an error here.