class OpaqueBaseMeta(type): def __instancecheck__(cls, instance): if super().__instancecheck__(instance): return True if hasattr(instance, "real_obj"): from torch._library.fake_class_registry import FakeScriptObject if isinstance(instance, FakeScriptObject): return super().__instancecheck__(instance.real_obj) return False class OpaqueBase(metaclass=OpaqueBaseMeta): pass