Drop code for Python 2.3.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@26000 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/CMFActivity/ActivityBuffer.py

@@ -32,10 +32,6 @@ try:
 except ImportError:
   pass
 
-# python2.3 compatibility
-if not hasattr(globals()['__builtins__'], 'set'):
-  from sets import Set as set
-
 class ActivityBuffer(TM):
 
   _p_oid=_p_changed=_registered=None