function setShippingMethod($data, $form)
 {
     $cart = $this->owner->Cart();
     $option = null;
     if (isset($data['ShippingMethodID'])) {
         $option = DataObject::get_by_id("ShippingMethod", (int) $data['ShippingMethodID']);
     }
     //assign option to order / modifier
     if ($option) {
         $checkout = new Checkout($cart);
         $checkout->setShippingMethod($option);
     }
     Director::redirect($this->NextStepLink('paymentmethod'));
 }