Gets the ASC rank of @member from the sorted set, that is,
            lower scores have lower ranks

def rank(self, member):
        """ Gets the ASC rank of @member from the sorted set, that is,
            lower scores have lower ranks
        """
        if self.reversed:
            return self._client.zrevrank(self.key_prefix, self._dumps(member))
        return self._client.zrank(self.key_prefix, self._dumps(member))