generics used in type aliases incorrectly cause `Expression type contains "Any"` error

[DetachHead]

from typing import _T as T, Generic

class A(Generic[T]):...

NG = A[T] # error: Expression type contains "Any" (has type "Type[A[Any]]")  [misc]

playground

[emmatyping]

I think the error is correct, but the issue is more that we should be giving an error about the type variable in a type alias.

[DetachHead]

@ethanhs why? it works just fine and it's a useful feature

MaybeList = Union[T, list[T]]

[KotlinIsland]

@ethanhs mypy supports generic type aliases https://mypy.readthedocs.io/en/stable/generics.html#generic-type-aliases