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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 doVerify(self):
 """Process the form submission, initating OpenID verification. """


        # First, make sure that the user entered something
        openid_url = self.query.get('openid_identifier')
        if not openid_url:
            self.render(
                'Enter an OpenID Identifier to verify.',
                css_class='error',
                form_contents=openid_url)
            return

        immediate = 'immediate' in self.query
        use_sreg = 'use_sreg' in self.query
        use_pape = 'use_pape' in self.query
        use_stateless = 'use_stateless' in self.query
        oidconsumer = self.getConsumer(stateless=use_stateless)
        try:
            request = oidconsumer.begin(openid_url)
        except consumer.DiscoveryFailure as exc:
            fetch_error_string = 'Error in discovery: %s' % (
                cgi.escape(str(exc)))
            self.render(
                fetch_error_string,
                css_class='error',
                form_contents=openid_url)
        else:
            if request is None:
                msg = 'No OpenID services found for <code>%s</code>' % (
                    cgi.escape(openid_url), )
                self.render(msg, css_class='error', form_contents=openid_url)
            else:
                # Then, ask the library to begin the authorization.
                # Here we find out the identity server that will verify the
                # user's identity, and get a token that allows us to
                # communicate securely with the identity server.
                if use_sreg:
                    self.requestRegistrationData(request)

                if use_pape:
                    self.requestPAPEDetails(request)

                trust_root = self.server.base_url
                return_to = self.buildURL('process')
                if request.shouldSendRedirect():
                    redirect_url = request.redirectURL(
                        trust_root, return_to, immediate=immediate)
                    self.send_response(302)
                    self.send_header('Location', redirect_url)
                    self.writeUserHeader()
                    self.end_headers()
                else:
                    form_html = request.htmlMarkup(
                        trust_root,
                        return_to,
                        form_tag_attrs={'id': 'openid_message'},
                        immediate=immediate)

                    self.wfile.write(bytes(form_html, 'utf-8'))