def METHOD_NAME(self):
    responses.add(
        responses.GET,
        f'{settings.REMOTE_SETTINGS_WRITER_URL}__heartbeat__',
        status=503,
        body=json.dumps({'check': False}),
    )
    responses.add(
        responses.GET,
        settings.REMOTE_SETTINGS_WRITER_URL,
        status=200,
        body=json.dumps({}),
    )
    obtained, _ = monitors.remotesettings()
    assert '503 Server Error: Service Unavailable' in obtained