diff --git a/test/test_echo_to_stream.py b/test/test_echo_to_stream.py
index b97c519..96c99e1 100644
--- a/test/test_echo_to_stream.py
+++ b/test/test_echo_to_stream.py
@@ -1,4 +1,5 @@
 import os
+import sys
 if sys.version_info >= (3.0, 0.0):
     from unittest.mock import MagicMock
 else: