def METHOD_NAME(self):
    def do_fetch_versions():
        try:
            return fetch_versions(BUILD_TYPE)
        except UpdateError:
            print_exc()
            return None
    cancel = Cancellable()
    self.connect("response", self._on_response, cancel)
    call_async(do_fetch_versions, cancel, self._on_result)
    return super().METHOD_NAME()