convert shebang lines: python -> python3
diff --git a/Tools/scripts/ndiff.py b/Tools/scripts/ndiff.py
index c60c8a8..2422091 100755
--- a/Tools/scripts/ndiff.py
+++ b/Tools/scripts/ndiff.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Module ndiff version 1.7.0
 # Released to the public domain 08-Dec-2000,