diff --git a/src/gen-os2-unicode-ranges.py b/src/gen-os2-unicode-ranges.py
old mode 100644
new mode 100755
index 95f1f1156..515f4ca14
--- a/src/gen-os2-unicode-ranges.py
+++ b/src/gen-os2-unicode-ranges.py
@@ -1,3 +1,5 @@
+#!/usr/bin/python
+
 # -*- coding: utf-8 -*-
 
 # Generates the code for a sorted unicode range array as used in hb-ot-os2-unicode-ranges.hh