AdminSite.site_url
The URL for the “View site” link at the top of each admin page. By default, site_url is /. Set it to None to remove the link.
For sites running on a subpath, the each_context() method checks if the current request has request.META['SCRIPT_NAME'] set and uses that value if site_url isn’t set to something other than /.
Changed in Django 1.10: The SCRIPT_NAME support described in the previous paragraph was added.