diff --git a/test/function_test.py b/test/function_test.py
index 1ebc383..06f9ecd 100644
--- a/test/function_test.py
+++ b/test/function_test.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 """
 >>> import os
+>>> import sys
 >>> import time
 >>> import nava
 >>> nava.play(os.path.join("others", "test.wav"))