def vin_api_url(vin, api_key='jUYdFF3AtxKqmuazznR2'):
    """
    URL of the service to retrieve VIN details, the service is passed
    {vin} and api_{key} params, if no key passed, default api key will be used
    :param vin: VIN number
    :param api_key: Third-party API service key,
    the service requires an authorization to get the key
    :return: URL string
    """
    return 'https://www.decodethis.com/webservices/decodes/' \
           '{vin}/{key}/1.json'.format(vin=vin, key=api_key)