code: def send_message(
              self,
              title=None,
              body=None,
              icon=None,
              data=None,
              sound=None,
              badge=None,
              api_key=None,
              **kwargs):
          
          if self:
              from .fcm import fcm_send_bulk_message
  
              registration_ids = list(self.filter(active=True).values_list(
                  'registration_id',
                  flat=True
              ))
              if len(registration_ids) == 0:
                  return [{'failure': len(self), 'success': 0}]
  
              result = fcm_send_bulk_message(
                  registration_ids=registration_ids,
                  title=title,
                  body=body,
                  icon=icon,
                  data=data,
                  sound=sound,
                  badge=badge,
                  api_key=api_key,
                  **kwargs
              )
  
              self._deactivate_devices_with_error_results(
                  registration_ids,
                  result['results']
              )
              return result
docs: Send notification for all active devices in queryset and deactivate if
          DELETE_INACTIVE_DEVICES setting is set to True.