[Python] Map one type to another and make type checker understand

I have the following piece of code:

from typing import Any

class RawA:
pass

class A:
pass

class RawB:
pass

class B:
pass

# Example of a kind of mapping (that doesn't work)
mapping = {
RawA: A,
RawB: B
}


def unraw[TRaw: Any](obj: TRaw) -> Any # -> the unraw type
...


Now how would I create some sort of mapping (of course a dictionary like here won't work) that the type checker then uses to find the appropriate return type?

For example, if I pass an instance of RawA into my function, the type checker understands the return value will be an instance of the type RawA is mapped to, in this case A.

I know could just exhaust all possibilities via overloads, but that is way to cumbersome and error prone for my case.

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