code: def _update_record(self, identifier, rtype=None, name=None, content=None):
          
          record_ids = []
          if not identifier:
              records = self._list_records(rtype, name)
              record_ids = [record['id'] for record in records]
          else:
              record_ids.append(identifier)
  
          for an_identifier in record_ids:
              opts = {'id': an_identifier}
              if rtype is not None:
                  opts['type'] = rtype.upper()
              if name is not None:
                  opts['name'] = self._full_name(name)
              if content is not None:
                  opts['content'] = content
              opts.update(self._auth)
  
              response = self._api.nameserver.updateRecord(opts)
              self._validate_response(
                  response=response, message='Failed to update record',
                  exclude_code=2302)
  
          return True
docs: update a record
  
          :param int identifier: identifier of record to update
          :param str rtype: type of record
          :param str name: name of record
          :param mixed content: value of record
          :return bool: success status
          :raises Exception: on error