Use an iterator for better performance.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@26401 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/Base.py

@@ -900,7 +900,7 @@ class Base( CopyContainer,
       portal_types = getToolByName(portal, 'portal_types', None)
       generated_bid = {}
       econtext = createExpressionContext(object=self, portal=portal)
-      for pid, ps in PropertySheet.__dict__.items():
+      for pid, ps in PropertySheet.__dict__.iteritems():
         if pid[0] != '_':
           base_category_list = []
           for cat in getattr(ps, '_categories', ()):