code: def update_ptr_record(self, device, record, domain_name, data=None,
              ttl=None, comment=None):
          
          device_type = self._resolve_device_type(device)
          href, svc_name = self._get_ptr_details(device, device_type)
          try:
              rec_id = record.id
          except AttributeError:
              rec_id = record
          rec = {"name": domain_name,
                "id": rec_id,
                "type": "PTR",
                "data": data,
              }
          if ttl is not None:
              # Minimum TTL is 300 seconds
              rec["ttl"] = max(300, ttl)
          if comment is not None:
              # Maximum comment length is 160 chars
              rec["comment"] = comment[:160]
          body = {"recordsList": {
                      "records": [rec]},
                  "link": {
                      "content": "",
                      "href": href,
                      "rel": svc_name,
                  }}
          uri = "/rdns"
          try:
              resp, resp_body = self._async_call(uri, body=body, method="PUT",
                      has_response=False, error_class=exc.PTRRecordUpdateFailed)
          except exc.EndpointNotFound as e:
              raise exc.InvalidPTRRecord("The record domain/IP address "
                      "information is not valid for this device.")
          return resp_body.get("status") == "COMPLETED"
docs: Updates a PTR record with the supplied values.