pyramid save off url in forbidden view

__init__.py

def redirect_if_not_logged_in(request):
    if request.user is None:
        request.session['original_url'] = request.url
        return HTTPFound(location=request.route_url(
                request.registry.settings['auth.login_route_name']))
    return Forbidden()


def main(global_config, **settings):
    #...
    config.add_view(redirect_if_not_logged_in, context=Forbidden,
        permission=NO_PERMISSION_REQUIRED)