docs: def __get_metrics(self):
          """ Each metric must have its own filters copy to modify it freely"""
          esfilters_merge = None
          esfilters_abandon = None
          if self.esfilters:
              esfilters_merge = self.esfilters.copy()
              esfilters_abandon = self.esfilters.copy()
  
          merged = Merged(self.es_url, self.es_index,
                          start=self.start, end=self.end,
                          esfilters=esfilters_merge, interval=self.interval)
  
          abandoned = Abandoned(self.es_url, self.es_index,
                                start=self.start, end=self.end,
                                esfilters=esfilters_abandon, interval=self.interval)
          return (merged, abandoned)