m ,Ec@sdZdklZydklZWn+dklZeddklZnXeZdkl Z dk Z e i de i d>> from persistent import Persistent >>> from persistent.list import PersistentList >>> from persistent.mapping import PersistentMapping 2. You want your classes to be ExtensionClasses. In this case, you need to install the ExtensionClass package separately. ExtensionClass is no-longer included with ZODB3. (sPersistentMappingNt PersistencetBoboPOSsPersistence.mappingsBoboPOS.PersistentMapping( t__doc__t persistentt PickleCachet _Persistencet Persistenttwarningstwarnt OverridabletPersistence.mappingtPersistentMappingtsystmodules(R R RRR R((t3/data/zmath/zope/lib/python/Persistence/__init__.pyt?s