diff --git a/edtanous/rootfs_size.py b/edtanous/rootfs_size.py
index 7d6ef85..c7942c3 100755
--- a/edtanous/rootfs_size.py
+++ b/edtanous/rootfs_size.py
@@ -1,3 +1,5 @@
+#!/usr/bin/python3
+
 import subprocess
 import tempfile
 import os