def METHOD_NAME(self):
    original_url = self._make_absolute_url(request.args['original_url'])
    shortcut = request.form['shortcut'].strip()
    if not (set(shortcut) <= CUSTOM_SHORTCUT_ALPHABET):
        raise BadRequest('Invalid shortcut')
    result = register_shortcut(original_url, shortcut, session.user)
    if result.get('error'):
        kwargs = {'success': False, 'msg': self._get_error_msg(result)}
    else:
        kwargs = {'success': True, 'shorturl': result['short_url']}
    return jsonify_template('ursh_custom_shortener_page.html', render_plugin_template,
                            event=self.event, ursh_host=self.ursh_host, shortcut=shortcut,
                            original_url=original_url, submitted=True, **kwargs)