[ZODB-Dev] ZODB3.3.0b1 and ExtensionClass?

[Tim Peters]

[Jim Fulton, with notes about ExtensionClass vs ZODB 3.3]

Jim, trying to import Persistence using current ZODB 3.3 yields this
message, where #2 now appears to be quite a project (to judge from
Christian's lack of luck so far):

"""
>>> import Persistence
C:\code\zodb\src\Persistence\__init__.py:25: UserWarning: Couldn't import
the ExtensionClass-based base class

    There are two possibilities:

    1. You don't care about ExtensionClass. You are importing
       Persistence because that's what you imported in the past.
       In this case, you should really use the persistent package
       instead:

          >>> 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.


  warn("""Couldn't import the ExtensionClass-based base class
>>>
"""

Is it our intent now that there *be* a (sanely installable) "ExtensionClass
package", or should I replace that part of the msg by, e.g., a link to your
reply to Christian?