add missing imports.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@30662 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5/mixin/rule.py

@@ -28,6 +28,8 @@
 
 import zope.interface
 from AccessControl import ClassSecurityInfo
+from Acquisition import aq_base
+from Products.CMFCore.utils import getToolByName
 from Products.ERP5Type import Permissions, interfaces
 
 def _compare(tester_list, prevision_movement, decision_movement):