diff --git a/build/parse_strace_open.py b/build/parse_strace_open.py
index 5dd878b..a971220 100755
--- a/build/parse_strace_open.py
+++ b/build/parse_strace_open.py
@@ -1,4 +1,5 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+#
 # Copyright 2019 The Hafnium Authors.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");