Fixed up the introspection code and tests added for #9779 to run under Python...

Fixed up the introspection code and tests added for #9779 to run under Python 2.3, which has neither set nor rsplit.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@10392 bcc190cf-cafb-0310-a4f2-bffc1f526a37