{"version":"1.0","type":"rich","title":"Nav mixin","description":"This example shows a Django mixin for generating hierarchical navigation menus from a model tree, rendering nested `<ul>` and `<li>` structures with links or selected/ancestor states. The code uses `django.core.urlresolvers.reverse` for URL generation, `django.contrib.admin.site` for admin integration, and `django.utils.safestring.mark_safe` for safe HTML output. It relies on MPTT model methods like `get_ancestors`, `get_children`, and `get_siblings` to traverse the tree, filtering by `active` and `show_in_navigation` fields. The output is a string of nested HTML tags, with the current page rendered as a `<span>` and ancestors highlighted with CSS classes.","provider_name":"VizHub AI Studio","provider_url":"https://next.vizhub.com","html":"<iframe src=\"https://next.vizhub.com/viz/gist-1084222?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"1\"></iframe>","width":960,"height":500,"cache_age":3600}