def METHOD_NAME(timer_client, start, interval):
    meta = load_response(timer_client.create_job).metadata
    transfer_data = TransferData(
        source_endpoint=GO_EP1_ID, destination_endpoint=GO_EP2_ID
    )
    timer_job = TimerJob.from_transfer_data(transfer_data, start, interval)
    response = timer_client.create_job(timer_job)
    assert response.http_status == 201
    assert response.data["job_id"] == meta["job_id"]
    timer_job = TimerJob.from_transfer_data(dict(transfer_data), start, interval)
    response = timer_client.create_job(timer_job)
    assert response.http_status == 201
    assert response.data["job_id"] == meta["job_id"]
    req_body = json.loads(get_last_request().body)
    if isinstance(start, datetime.datetime):
        assert req_body["start"] == start.isoformat()
    else:
        assert req_body["start"] == start
    if isinstance(interval, datetime.timedelta):
        assert req_body["interval"] == interval.total_seconds()
    else:
        assert req_body["interval"] == interval
    assert req_body["callback_url"] == slash_join(
        get_service_url("actions"), "/transfer/transfer/run"
    )