Use string.ascii_letters instead of string.letters (SF bug #226706).
diff --git a/Mac/scripts/gensuitemodule.py b/Mac/scripts/gensuitemodule.py
index b68def7..6549ed2 100644
--- a/Mac/scripts/gensuitemodule.py
+++ b/Mac/scripts/gensuitemodule.py
@@ -825,7 +825,7 @@
 	if not str:
 		return "_empty_ae_name"
 	rv = ''
-	ok = string.letters  + '_'
+	ok = string.ascii_letters + '_'
 	ok2 = ok + string.digits
 	for c in str:
 		if c in ok: