code: def count_objects_by_tags(self, metric, scraper_config):
          
          config = self.object_count_params[metric.name]
          metric_name = "{}.{}".format(scraper_config['namespace'], config['metric_name'])
          object_counter = Counter()
  
          for sample in metric.samples:
              tags = [
                  self._label_to_tag(l, sample[self.SAMPLE_LABELS], scraper_config) for l in config['allowed_labels']
              ] + scraper_config['custom_tags']
              object_counter[tuple(sorted(tags))] += sample[self.SAMPLE_VALUE]
  
          for tags, count in iteritems(object_counter):
              self.gauge(metric_name, count, tags=list(tags))
docs: Count objects by whitelisted tags and submit counts as gauges.