ParamSpec doesn't work in generic type aliases

[CyanoKobalamyne]

Bug Report

Generic type aliases where one of the free "type variables" is a ParamSpec don't work.

To Reproduce

1. test.py:

   from typing import Callable, TypeVar
   
   from typing_extensions import ParamSpec
   
   
   P = ParamSpec("P")
   R = TypeVar("R")
   
   FunctionType = Callable[P, R]
   
   
   def a_decorator(func: FunctionType[[int], str]) -> None:
       ...
   

2. mypy test.py

Expected Behavior

This should not raise any errors. A similar example. where both type variables are actual TypeVars, works:

from typing import Dict, TypeVar


K = TypeVar("K")
V = TypeVar("V")

DictType = Dict[K, V]


def a_function(d: DictType[int, str]) -> None:
    ...

Actual Behavior

Output:

test.py:9: error: The first argument to Callable must be a list of types or "..."
test.py:12: error: Bracketed expression "[...]" is not valid as a type
test.py:12: note: Did you mean "List[...]"?
test.py:12: error: Bad number of arguments for type alias, expected: 0, given: 2

Your Environment

• Mypy version used: 0.950
• Mypy command-line flags: none
• Mypy configuration options from mypy.ini (and other config files): none
• Python version used: 3.7.11
• Operating system and version: macOS 12.3.1

[cdce8p]

Duplicate of #11855

[CyanoKobalamyne]

Oops, sorry, for some reason I could not find that issue with the keywords I was searching for.