def keys(self):
        logger.warn('listing all keys is slow and should be used sparsely')
        keys = self.get_keys()
        fields = []
        for key in keys:
            more_fields = self.redis.hkeys(key)
            fields += more_fields
        return fields
Return a registry key's parent key if it exists
dataset/ETHPy150Open tschellenbach/Stream-Framework/stream_framework/storage/redis/structures/hash.py/ShardedHashCache.keys--crossover with--dataset/ETHPy150Open tjguk/winsys/winsys/registry.py/parent