def is_owner(self, obj):
        ct = ContentType.objects.get_for_model(obj)
        try:
            ooentry = self.objectaccess_set.get(
                content_type=ct, object_id=obj.id)
        except ObjectAccess.DoesNotExist:
            return False
        return ooentry.is_owner
Tell is the user is the unique owner of this object
dataset/ETHPy150Open tonioo/modoboa/modoboa/core/models.py/User.is_owner