One last final fix for 0ad76843. Tested on py3 and py2

tests/regressiontests/i18n/tests.py

@@ -957,8 +957,7 @@ class TestLanguageInfo(TestCase):
         self.assertEqual(li['bidi'], False)
 
     def test_unknown_language_code(self):
-        with self.assertRaisesRegexp(KeyError, "Unknown language code xx."):
-            get_language_info('xx')
+        six.assertRaisesRegex(self, KeyError, "Unknown language code '?xx'?.", get_language_info, 'xx-xx')
 
     def test_unknown_only_country_code(self):
         li = get_language_info('de-xx')
@@ -968,8 +967,7 @@ class TestLanguageInfo(TestCase):
         self.assertEqual(li['bidi'], False)
 
     def test_unknown_language_code_and_country_code(self):
-        with self.assertRaisesRegexp(KeyError, "Unknown language code xx-xx and xx."):
-            get_language_info('xx-xx')
+        six.assertRaisesRegex(self, KeyError, "Unknown language code '?xx-xx'? and '?xx'?.", get_language_info, 'xx-xx')
 
 
 class MultipleLocaleActivationTests(TestCase):