code: def list_resource_record_sets(self, max_results=None, page_token=None, client=None):
          
          client = self._require_client(client)
          path = "/projects/%s/managedZones/%s/rrsets" % (self.project, self.name)
          iterator = page_iterator.HTTPIterator(
              client=client,
              api_request=client._connection.api_request,
              path=path,
              item_to_value=_item_to_resource_record_set,
              items_key="rrsets",
              page_token=page_token,
              max_results=max_results,
          )
          iterator.zone = self
          return iterator
docs: List resource record sets for this zone.
  
          See
          https://cloud.google.com/dns/api/v1/resourceRecordSets/list
  
          :type max_results: int
          :param max_results: Optional. The maximum number of resource record
                              sets to return. Defaults to a sensible value
                              set by the API.
  
          :type page_token: str
          :param page_token: Optional. If present, return the next batch of
              resource record sets, using the value, which must correspond to
              the ``nextPageToken`` value returned in the previous response.
              Deprecated: use the ``pages`` property of the returned iterator
              instead of manually passing the token.
  
          :type client: :class:`google.cloud.dns.client.Client`
          :param client:
              (Optional) the client to use.  If not passed, falls back to the
              ``client`` stored on the current zone.
  
          :rtype: :class:`~google.api_core.page_iterator.Iterator`
          :returns: Iterator of :class:`~.resource_record_set.ResourceRecordSet`
                    belonging to this zone.