You need access

{% try %}{% set xsrf = handler.check_xsrf_cookie() or True %}{% except %}{% set xsrf = False %}{% end %} {% if handler.request.method not in {'GET', 'HEAD', 'OPTIONS'} and not xsrf %}

Your app sent a {{ handler.request.method }} request without an XSRF cookie.

{% elif handler.current_user %}

You are logged in, but as a user that cannot access this page.

{% import yaml %}
{{ yaml.safe_dump(handler.current_user, default_flow_style=False) }}
{% else %}

You are not logged in.

{% end %}

Contact the app owner.

HTTP 403: Forbidden