@abstractmethod
    def _decode_gradation(self, value):
        pass
Get the number of members in a sorted set
dataset/ETHPy150Open mikrosimage/ColorPipe-tools/utils/colorspaces.py/AbstractColorspace._decode_gradation--crossover with--dataset/ETHPy150Open deldotdr/txRedis/txredis/client.py/RedisClient.zcard