Add comment to Distutil files about requiring 1.5.2 compatibility, as
    suggested by PEP 291.
diff --git a/Lib/distutils/command/clean.py b/Lib/distutils/command/clean.py
index 36252d5..41b2277 100644
--- a/Lib/distutils/command/clean.py
+++ b/Lib/distutils/command/clean.py
@@ -4,6 +4,8 @@
 
 # contributed by Bastian Kleineidam <calvin@cs.uni-sb.de>, added 2000-03-18
 
+# This module should be kept compatible with Python 1.5.2.
+
 __revision__ = "$Id$"
 
 import os