docs: def change_score_for_member_in(self, leaderboard_name, member, delta, member_data=None):
          '''
          Change the score for a member in the named leaderboard by a delta which can be positive or negative.
  
          @param leaderboard_name [String] Name of the leaderboard.
          @param member [String] Member name.
          @param delta [float] Score change.
          @param member_data [String] Optional member data.
          '''
          previous_score = self.score_for(member)
          new_score = (previous_score or 0) + delta
  
          total_members_at_previous_score = []
          if previous_score is not None:
              total_members_at_previous_score = self.redis_connection.zrevrangebyscore(leaderboard_name, previous_score, previous_score)
  
          pipeline = self.redis_connection.pipeline()
          if isinstance(self.redis_connection, Redis):
              pipeline.zadd(leaderboard_name, member, new_score)
              pipeline.zadd(self._ties_leaderboard_key(leaderboard_name), str(float(new_score)), new_score)
          else:
              pipeline.zadd(leaderboard_name, new_score, member)
              pipeline.zadd(self._ties_leaderboard_key(leaderboard_name), new_score, str(float(new_score)))
          if member_data:
              pipeline.hset(
                  self._member_data_key(leaderboard_name),
                  member,
                  member_data)
          pipeline.execute()
  
          if len(total_members_at_previous_score) == 1:
              self.redis_connection.zrem(self._ties_leaderboard_key(leaderboard_name), str(float(previous_score)))