Collector #771: using instance()

lib/python/Products/ZCatalog/Catalog.py

@@ -44,7 +44,7 @@ except:
             if hasattr(ob, '__call__'):
                 return 1
             else:
-                return type(ob) in [types.ClassType]
+                return isinstance(ob, types.ClassType)
         else:
             return callable(ob)