def filter_handlers(handler_cls: BaseValidateHandlerProtocol, method_name: str) -> bool:
    """Filter out handler methods which are not implemented by the plugin directly - e.g. are missing
    or are inherited from the protocol.
    """
    handler = getattr(handler_cls, method_name, None)
    if handler is None:
        return False
    elif handler.__module__ == 'pydantic.plugin':
        # this is the original handler, from the protocol due to runtime inheritance
        # we don't want to call it
        return False
    else:
        return True
Filter out handler methods which are not implemented by the plugin directly - e.g. are missing
    or are inherited from the protocol.
    
pydantic/plugin/_schema_validator.py