Get parent classes' type annotations on inherited class instance

Python Help
1

In the following code:

class A[T]:
    a: T

class B[T, P](A[T]):
    b: P

B[int, str]().__annotations__ # {'b': P}

Is there a way to get the full annotations? i.e.

{'a': T, 'b': P}
2

Self solved:

Instead of accessing __annotations__, use typing.get_type_hints() on the class. Not instance.

from typing import get_type_hints

# CORRECT
get_type_hints(B) # {'a': T, 'b': P}

# All these below are WRONG
get_type_hints(B()) # {'b': P}
B.__annotations__   # {'b': P}
B().__annotations__ # {'b': P}
3

Note that B.__annotations__ can be correct if you truly only want the annotations directly on class for e.g. a dataclass-like. But accessing it on an instance is always wrong.

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