[Python] @cached decorator breaks method signature inheritance in subclass

I’m using @cached from aiocache on an overridden async method in a subclass. The parent class has a method with a specific return type, and the subclass overrides it with the same return type. But after decorating the subclass method with @cached, I get a type error from pylance:

"get_all" overrides method of same name in class "IBaseRepository" with incompatible type "_Wrapped[..., Unknown, ..., CoroutineType[Any, Any, Unknown]]"



Code example:

from aiocache import cached

# Base repository
class IBaseRepository(Generic[T]):
async def get_all(self) -> List[T]:
...

# Concrete repository
class CategoryRepositoryImpl(IBaseRepository[CategoryDomain]):
@cached(ttl=600, key_builder=classaware_key_builder)
async def get_all(self) -> List[CategoryDomain]:
return await super().get_all()


Even if I move caching logic entirely outside the repository method into a use-case or service layer function, applying @cached as a decorator still breaks the function’s signature from the type checker’s perspective.

If it matters, caching is performed using Redis.

After adding the @cached decorator, my type checker complains that the method signature is now incompatible. Is there a typing-friendly way to use @cached on subclass methods without breaking method signature inheritance? Or is there a recommended pattern for caching that avoids this problem in type-checked Python code?

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