old_contents: from django.conf.urls import patterns, url
  from oscar.core.application import Application
  
  from systempay import views
  
  
  class SystemPayApplication(Application):
      name = 'systempay' 
  
      place_order_view = views.PlaceOrderView
      cancel_response_view = views.CancelResponseView
      secure_redirect_view = views.SecureRedirectView
  
      def __init__(self, *args, **kwargs):
          super(SystemPayApplication, self).__init__(*args, **kwargs)
  
      def get_urls(self):
          urlpatterns = super(SystemPayApplication, self).get_urls()
          urlpatterns += patterns('',
              url(r'^secure-redirect/', self.secure_redirect_view.as_view(), name='secure-redirect'),
              url(r'^preview/', self.place_order_view.as_view(preview=True),
                  name='preview'),
              url(r'^cancel/', self.cancel_response_view.as_view(),
                  name='cancel-response'),
              url(r'^place-order/', self.place_order_view.as_view(),
                  name='place-order'),
              # View for using PayPal as a payment method
              # url(r'^handle-ipn/', self.redirect_view.as_view(as_payment_method=True),
              #     name='systempay-direct-payment'),
          )
          return self.post_process_urls(urlpatterns)
  
  
  application = SystemPayApplication()
  
new_contents: from django.conf.urls import patterns, url
  from oscar.core.application import Application
  
  from systempay import views
  
  
  class SystemPayApplication(Application):
      name = 'systempay' 
  
      place_order_view = views.PlaceOrderView
      cancel_response_view = views.CancelResponseView
      secure_redirect_view = views.SecureRedirectView
      handle_ipn_view = views.HandleIPN
  
      def __init__(self, *args, **kwargs):
          super(SystemPayApplication, self).__init__(*args, **kwargs)
  
      def get_urls(self):
          urlpatterns = super(SystemPayApplication, self).get_urls()
          urlpatterns += patterns('',
              url(r'^secure-redirect/', self.secure_redirect_view.as_view(), name='secure-redirect'),
              url(r'^preview/', self.place_order_view.as_view(preview=True),
                  name='preview'),
              url(r'^cancel/', self.cancel_response_view.as_view(),
                  name='cancel-response'),
              url(r'^place-order/', self.place_order_view.as_view(),
                  name='place-order'),
              url(r'^handle-ipn/', self.handle_ipn_view.as_view(),
                  name='handle-ipn'),
          )
          return self.post_process_urls(urlpatterns)
  
  
  application = SystemPayApplication()
  
subject: Add missing handle ipn url