Use validator if user is linked with a person.

biscuit/apps/untis/menus.py

@@ -5,7 +5,7 @@ MENUS = {
         {
             'name': _('Units import'),
             'url': 'untis_import',
-            'validators': ['menu_generator.validators.is_authenticated', 'menu_generator.validators.is_superuser'],
+            'validators': ['menu_generator.validators.is_authenticated', 'menu_generator.validators.is_superuser', 'biscuit.core.util.core_helpers.has_person'],
         }
     ]
 }