Not inferring generic type for variable typed as Callable with TypeVar

[xhantu]

Describe the Bug

from typing import *

T = TypeVar('T')
f: Callable[[T], T] = lambda x: x
reveal_type(f)
r: int = f(1)

INFO sandbox.py:5:12-15: revealed type: (TypeVar[T]) -> TypeVar[T] [reveal-type]
ERROR sandbox.py:6:10-14: `TypeVar[T]` is not assignable to `int` [bad-assignment]
ERROR sandbox.py:6:12-13: Argument `Literal[1]` is not assignable to parameter with type `TypeVar[T]` [bad-argument-type]

Python: 3.12

The type of f should be [T](T) -> T and not (TypeVar[T]) -> TypeVar[T]

Because of this the usage of f fails with type errors.

Sandbox Link

https://pyrefly.org/sandbox/?project=N4IgZglgNgpgziAXKOBDAdgEwEYHsAeAdAA4CeS4ATrgLYAEALqcROgOZ0Q3G6UN0AqADroRAFToBeOmOYwAaqkoAKAORjVAShFhEdAMKooUVNlgBtc2IC6AGhnWpdEzWyZUdfHvwjKMAG4wRgD6TMQwymDa6JR6rPzSYMoAjJogtiAArgzQcCTkiCAAxHQAqjlQEEx0YJnoAMY5uOhwIiKYMGA1vDSoDMHoma4wKl6c6AyadAC0AHx0cAyxInSrdH4MmZToNUIgAHJD2CN6wPgAvnsi6SBkfmBQpIQMtFAUJQAKpPePCxg4BDo9WakDYWz6EGahBEJQAyjAYHQABYMBjEOCIAD0mLunUehF4bExMHQmMwuHqcExwPQoPBTVJ3UodFQ-lQ0FMsCBIIgYMoEOadFwxAZeREZAYSOa00ClDgkJ20j2AGZCMkAExXdAgc4ZVCNCCBABi0BgFDQWDwRDIOqAA

(Only applicable for extension issues) IDE Information

No response

[yangdanny97]

The bug appears to be that we're not checking the type annotation for type variables & inferring a generic type from it.

[bluetech]

Real-life examples from django-stubs in case it helps in any way:
https://github.com/typeddjango/django-stubs/blob/f788f6ce9833c6805bad7a3cd19c77893b9f9063/django-stubs/views/decorators/http.pyi