[Python] How to specify generic python signature to return type, as well as use type in...

I'm trying to write a function which takes a class as an argument, returns an instance of that class wrapped in another type, and uses the type of the class for casting internally, it works with a simple type like str, but not an actual class.

I've reduced this code to the point that it's a bit silly to be using generics but it demonstrates my problem at least.

from typing import cast, Type, TypeVar, Generic, Optional, Any
from pydantic import BaseModel, UUID4
from typing_extensions import Annotated, TypeAliasType
from pydantic.functional_validators import BeforeValidator
from uuid import UUID

def api_fn(output_cls: Optional[Type[BaseModel]] = None):
return None # simplified for example code, signature cannot be changed, not my code

def amount_f(v: Any) -> float:
return 0.0 # simplified for example code

MyNumber = Annotated[float, BeforeValidator(amount_f)]

DataT = TypeVar('DataT')
class TypeWithId(BaseModel, Generic[DataT]):
value: DataT
id: UUID4

T = TypeVar('T')
OptionalWithId = TypeAliasType(
'OptionalWithId', Optional[TypeWithId[T]], type_params=(T,)
)

OutT = TypeVar('OutT')
def query(output_cls:Type[OutT]) -> OptionalWithId[OutT]:
ret = api_fn(output_cls=output_cls)
return TypeWithId(value=cast(OutT,ret), id=UUID('00000000-0000-0000-0000-000000000000'))

str_result = query(str)
print(str_result)
number_result = query(MyNumber)
print(number_result)


The str_result works but the number_result gives me:

27 26 error e-f-b Pyright [reportArgumentType]: Argument of type "type[OutT@query]" cannot be assigned to parameter "output_cls" of type "type[BaseModel] | None" in function "api_fn"
32 0 error e-f-b Pyright [reportUnknownVariableType]: Type of "number_result" is partially unknown
32 22 error e-f-b Pyright [reportArgumentType]: Argument of type "MyNumber" cannot be assigned to parameter "output_cls" of type "type[OutT@query]" in function "query"
33 6 error e-f-b Pyright [reportUnknownArgumentType]: Argument type is partially unknown

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