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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 redirect_to_express(self):
 """ First step of ExpressCheckout. Redirect the request to PayPal using the data returned from setExpressCheckout. """

        wpp = PayPalWPP(self.request)
        try:
            nvp_obj = wpp.setExpressCheckout(self.item)
        except PayPalFailure:
            warn_untested()
            self.context['errors'] = self.errors['paypal']
            return self.render_payment_form()
        else:
            return HttpResponseRedirect(express_endpoint_for_token(nvp_obj.token))