[Python] How to typehint functools.partial classes

I'm struggling to type hint correctly a python dataclass (or any class) with partial initialization, it seems that the type is lost somewhere but not sure where:

from dataclasses import dataclass
from functools import partial
@dataclass
class Test:
a : int
b : int

@classmethod
def test_partial[T: Test](cls: type[T], b:int) -> partial[T]:
return partial(cls, b=b)

@classmethod
def test_partial2(cls, b:int):
return partial(cls, b=b)

part = Test.test_partial(3)
part( # linter suggest nothing when passing here

part2 =partial(Test, b=3)
part2( # linter suggest a=...,b=... when passing

# interestingly enough letting out the typehint, the linter knows again

part = Test.test_partial2(3)
part( # linter suggest a=...,b=... when passing




The interesting thing is that both mypy and typeright get's it right when I don't give it to them, so probably there is a way. Any clue?

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