code: def _get_cloud_zones(self, page_token=None):
          
  
          gcloud_zones = self.gcloud_client.list_zones(page_token=page_token)
          for gcloud_zone in gcloud_zones:
              self._gcloud_zones[gcloud_zone.dns_name] = gcloud_zone
  
          if gcloud_zones.next_page_token:
              self._get_cloud_zones(gcloud_zones.next_page_token)
docs: Load all ManagedZones into the self._gcloud_zones dict which is
          mapped with the dns_name as key.
  
          :return: void