diff --git a/image_conf/flash_build.py b/image_conf/flash_build.py
index d43ab601..e41dd88f 100644
--- a/image_conf/flash_build.py
+++ b/image_conf/flash_build.py
@@ -1,3 +1,4 @@
+#! /usr/bin/env python3
 # -*- coding:utf-8 -*-
 
 import os