code: def _batch_report(cls, request):
          
          if not newrelic:
              return
          metrics_cache = cls._get_metrics_cache()
          try:
              newrelic.agent.add_custom_parameter('user_id', request.user.id)
          except AttributeError:
              pass
          for key, value in metrics_cache.data.items():
              newrelic.agent.add_custom_parameter(key, value)
docs: Report the collected custom metrics to New Relic.