code: def validate_confirm_form(self):
          
          wpp = PayPalWPP(self.request)
          pp_data = dict(token=self.request.POST['token'], payerid=self.request.POST['PayerID'])
          self.item.update(pp_data)
  
          # @@@ This check and call could be moved into PayPalWPP.
          try:
              if self.is_recurring():
                  warn_untested()
                  nvp = wpp.createRecurringPaymentsProfile(self.item)
              else:
                  nvp = wpp.doExpressCheckoutPayment(self.item)
              self.handle_nvp(nvp)
          except PayPalFailure:
              self.context['errors'] = self.errors['processing']
              return self.render_payment_form()
          else:
              return HttpResponseRedirect(self.success_url)
docs: Third and final step of ExpressCheckout. Request has pressed the confirmation but
          and we can send the final confirmation to PayPal using the data from the POST'ed form.