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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 list_resource_record_sets(self, max_results=None, page_token=None, client=None):
 """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. """

        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