def default_payment_handler(request, order_form, order):
    """
    Default payment handler - called when the final step of the
    checkout process with payment information is submitted. Implement
    your own and specify the path to import it from via the setting
    ``SHOP_HANDLER_PAYMENT``. This function will typically contain
    integration with a payment gateway. Raise
    cartridge.shop.checkout.CheckoutError("error message") if payment
    is unsuccessful.
    """
    pass
