public byte[] RPopLPush(string fromListId, string toListId)
{
if (fromListId == null)
throw new ArgumentNullException("fromListId");
if (toListId == null)
throw new ArgumentNullException("toListId");
return SendExpectData(Commands.RPopLPush, fromListId.ToUtf8Bytes(), toListId.ToUtf8Bytes());
}