code: def set_stats_name(self, stats_name):
          
  
          if self.stats_name == stats_name:
              return
  
          if stats_name in scales._Stats.stats:
              raise ValueError('"{0}" already exists in stats.'.format(stats_name))
  
          stats = scales._Stats.stats[self.stats_name]
          del scales._Stats.stats[self.stats_name]
          self.stats_name = stats_name
          scales._Stats.stats[self.stats_name] = stats
docs: Set the metrics stats name.
          The stats_name is a string used to access the metris through scales: scales.getStats()[<stats_name>]
          Default is 'cassandra-<num>'.