@classmethod
    def strategy_for(cls, **kw):
        def decorate(dec_cls):
            # ensure each subclass of the strategy has its
            # own _strategy_keys collection
            if dec_cls.__dict__ not in '_strategy_keys':
                dec_cls._strategy_keys = []
            key = tuple(sorted(kw.items()))
            cls._all_strategies[cls][key] = dec_cls
            dec_cls._strategy_keys.append(key)
            return dec_cls
        return decorate
dataset/ETHPy150Open zzzeek/sqlalchemy/lib/sqlalchemy/orm/interfaces.py/StrategizedProperty.strategy_for/swapped operands of `not in`