Deprecate test.testall for removal in 3.0.
diff --git a/Lib/test/test_py3kwarn.py b/Lib/test/test_py3kwarn.py
index 0933382..c66ff73 100644
--- a/Lib/test/test_py3kwarn.py
+++ b/Lib/test/test_py3kwarn.py
@@ -126,6 +126,8 @@
 
 class TestStdlibRemovals(unittest.TestCase):
 
+    # test.testall not tested as it executes all unit tests as an
+    # import side-effect.
     all_platforms = ('audiodev', 'imputil', 'mutex', 'user', 'new')
 
     def check_removal(self, module_name):