--- a/web/views/uicfg.py	Wed Sep 16 11:23:51 2015 +0200
+++ b/web/views/uicfg.py	Mon Sep 14 16:03:07 2015 +0200
@@ -57,6 +57,8 @@
 
 from warnings import warn
 
+from six import string_types
+
 from cubicweb import neg_role
 from cubicweb.rtags import (RelationTags, RelationTagsBool, RelationTagsSet,
                             RelationTagsDict, NoTargetRelationTagsDict,
@@ -650,7 +652,7 @@
                 self.tag_relation((sschema, rschema, oschema, role), True)
 
     def _tag_etype_attr(self, etype, attr, desttype='*', *args, **kwargs):
-        if isinstance(attr, basestring):
+        if isinstance(attr, string_types):
             attr, role = attr, 'subject'
         else:
             attr, role = attr