Changed the tests added in r8898 very slightly so that they don't return

unintended results. Doctests aren't self-contained yet when run as part of
the full suite. Refs #5624, #8835.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@8930 bcc190cf-cafb-0310-a4f2-bffc1f526a37