# Return type is a union of tuples
def parse_resource_id() -> tuple[str, str] | tuple[None, None]:
    ...

# After destructuring, kind: str | None. The `not in` guard should narrow
# it to str, but pyrefly does not narrow via `not in`.
def lookup_resource(registry: dict[str, str]) -> str | None:
    kind, _obj_id = parse_resource_id()

    if kind not in registry:
        return None

    return registry[kind]  # Pyrefly: str | None not assignable to str key