Unpacking an iterable with an overloaded __iter__ method leads to variable silently being inferred as Any #14811

from typing import AnyStr, Generic, overload, Iterator

class Foo(Generic[AnyStr]):
    x: AnyStr
    @overload
    def __iter__(self: Foo[str]) -> Iterator[bytes]: ...
    @overload
    def __iter__(self: Foo[bytes]) -> Iterator[str]: ...
    def __iter__(self) -> Iterator[str | bytes]:
        if isinstance(self.x, str):
            yield from [b"a", b"b", b"c"]
        yield from ["a", "b", "c"]

a, b, c = Foo[str]()
reveal_type(a)  # note: Revealed type is "Any"