Add comment to Distutil files about requiring 1.5.2 compatibility, as
    suggested by PEP 291.
diff --git a/Lib/distutils/command/build.py b/Lib/distutils/command/build.py
index 0643948..7823154 100644
--- a/Lib/distutils/command/build.py
+++ b/Lib/distutils/command/build.py
@@ -2,6 +2,8 @@
 
 Implements the Distutils 'build' command."""
 
+# This module should be kept compatible with Python 1.5.2.
+
 __revision__ = "$Id$"
 
 import sys, os