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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_cloud_zones(self, page_token=None):
 """Load all ManagedZones into the self._gcloud_zones dict which is mapped with the dns_name as key. :return: void """


        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)