Issues when using pyright + multimethod

[bzm3r]

Consider the following little example:

from multimethod import multimethod


@multimethod
def normalize_index(index, labels: list[int]) -> int | slice | list[int]:
    raise Exception(f"No logic to normalize {index=} of {type(ix)=}")


@normalize_index.register(int | slice, list[int])
def _(index: int | slice, _: list[int]) -> int | slice | list[int]:
    return index

It produces the following errors for me, both on the line containing @normalize_index.register(int | slice, list[int]):

1. An issue with register, imported from multimethod:

Cannot access attribute "register" for class "_Wrapped[..., Unknown, ..., Unknown]"
  Attribute "register" is unknown

2. An issue with using UnionType for type:

Argument of type "UnionType" cannot be assigned to parameter "args" of type "type" in function "register"
  "UnionType" is incompatible with "type"

Is there anything I can do from my end to help these errors go away?

[erictraut]

I'm not familiar with this library. It looks like it contains some inline type annotations, but it's very incomplete. You could try creating your own stub file that is more complete. Short of that, there's probably not much you can do here to eliminate the static type errors.

[bzm3r]

Makes sense! I will address the errors then by simply not using it, as I don't have the time to contribute detailed type information post-hoc.