code: def contains(bank, key):
      '''
      Checks if the specified bank contains the specified key.
      '''
      redis_server = _get_redis_server()
      bank_redis_key = _get_bank_redis_key(bank)
      try:
          return redis_server.sismember(bank_redis_key, key)
      except (RedisConnectionError, RedisResponseError) as rerr:
          mesg = 'Cannot retrieve the Redis cache key {rkey}: {rerr}'.format(rkey=bank_redis_key,
                                                                             rerr=rerr)
          log.error(mesg)
          raise SaltCacheError(mesgf contains(bank, key):
      '''
      Checks if the specified bank contains the specified key.
      '''
      redis_server = _get_redis_server()
      bank_redis_key = _get_bank_redis_key(bank)
      try:
          return redis_server.sismember(bank_redis_key, key)
      except (RedisConnectionError, RedisResponseError) as rerr:
          mesg = 'Cannot retrieve the Redis cache key {rkey}: {rerr}'.format(rkey=bank_redis_key,
                                                                             rerr=rerr)
          log.error(mesg)
          raise SaltCacheError(mesg)
docs: Checks if the specified bank contains the specified key.