assertRaises can't be used as a context manager in 2.6.
diff --git a/Lib/test/test_warnings.py b/Lib/test/test_warnings.py
index 1f5d05f..71944cd 100644
--- a/Lib/test/test_warnings.py
+++ b/Lib/test/test_warnings.py
@@ -347,8 +347,7 @@
                 return ("A bad formatted string %(err)" %
                         {"err" : "there is no %(err)s"})
 
-        with self.assertRaises(ValueError):
-            self.module.warn(BadStrWarning())
+        self.assertRaises(ValueError, self.module.warn, BadStrWarning())
 
 
 class CWarnTests(BaseTest, WarnTests):