django-navutils | lightweight package for handling menus

I'm trying to allow for dynamic template tags. Specifically, I have a menu setup that I'm defining in code vs templates. And I would like to render the menu label as {{ request.user }}. So how can I define that as a string in Python, and allow the template to parse and render the string as intended. And not just variables too, templatetags as well ({% provider_login_url 'google' next=next %}).

What am I missing?

Update with code:

I'm specifically designing my menus with django-navutils, but that's less important (basically the package just stores the defined data and then uses templates to render it).