code: def process(self, endpoint, **kwargs):
          
          instance = kwargs.get('instance')
          if instance:
              kwargs['custom_tags'] = instance.get('tags', [])
  
          for metric in self.scrape_metrics(endpoint):
              self.process_metric(metric, **kwargs)
docs: Polls the data from prometheus and pushes them as gauges
          `endpoint` is the metrics endpoint to use to poll metrics from Prometheus
  
          Note that if the instance has a 'tags' attribute, it will be pushed
          automatically as additional custom tags and added to the metrics