[Python] How to use Generic (higher-level) type variables in type hinting system?

Suppose I want to write a generic class using mypy, but the type argument for the class is itself a generic type. For example:

from typing import TypeVar, Generic, Callable

A = TypeVar("A")
B = TypeVar("B")
T = TypeVar("T")


class FunctorInstance(Generic[T]):
def __init__(self, map: Callable[[Callable[[A], B], T[A]], T]):
self._map = map

def map(self, x: T[A], f: Callable[[A], B]) -> T:
return self._map(f, x)


When I try to call mypy in the definition above I get an error:

$ mypy typeclasses.py
typeclasses.py:9: error: Type variable "T" used with arguments
typeclasses.py:12: error: Type variable "T" used with arguments


I tried adding constraints to the T TypeVar's definition but failed to make this work. Is it possible to do this?

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