Patch by Christian Heimes to change self.assert_(x == y) into
self.assertEqual(x, y).  (Christian used self.failUnlessEqual(),
but the double negative makes it hard to grok, so I changed it.)
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 1f6499c..fe50e0c 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -53,7 +53,7 @@
         self.check_tempfile(name)
 
         name = os.tempnam(test_support.TESTFN, "pfx")
-        self.assert_(os.path.basename(name)[:3] == "pfx")
+        self.assertEqual(os.path.basename(name)[:3], "pfx")
         self.check_tempfile(name)
 
     def test_tmpfile(self):