Added 'normcase' function.

Lib/macpath.py

 # module 'macpath' -- pathname (or -related) operations for the Macintosh
 
+import string
 import mac
-
 from stat import *
 
 
+# Normalize the case of a pathname.  Dummy in Posix, but string.lower here.
+
+normcase = string.lower
+
+
 # Return true if a path is absolute.
 # On the Mac, relative paths begin with a colon,
 # but as a special case, paths with no colons at all are also relative.