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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate_confirm_form(self):
 """ 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. """

        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)