django-guardian 1.1.1 documentation
Removing object permissions is as easy as assigning them. Just instead of guardian.shortcuts.assign() we would use guardian.shortcuts.remove_perm() function (it accepts same arguments).
Let’s get back to our fellow Joe:
>>> site = Site.object.get_current()
>>> joe.has_perm('change_site', site)
True
Now, simply remove this permission:
>>> from guardian.shortcuts import remove_perm
>>> remove_perm('change_site', joe, site)
>>> joe = User.objects.get(username='joe')
>>> joe.has_perm('change_site', site)
False