T = TypeVar("T") P_2 = ParamSpec("P_2") class X(Generic[T, P]): f: Callable[P, int] x: T def f(x: X[int, P_2]) -> str: ... # Accepted def f(x: X[int, Concatenate[int, P_2]]) -> str: ... # Accepted def f(x: X[int, [int, bool]]) -> str: ... # Accepted def f(x: X[int, ...]) -> str: ... # Accepted def f(x: X[int, int]) -> str: ... # Rejected