As long as we're micro-optomizing, do it right -- using map() shaves another...

As long as we're micro-optomizing, do it right -- using map() shaves another dozen or so seconds off the test suite run time.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@11495 bcc190cf-cafb-0310-a4f2-bffc1f526a37