diff --git a/tests/lib.py b/tests/lib.py
index d77c3460..cadb86fe 100644
--- a/tests/lib.py
+++ b/tests/lib.py
@@ -16,7 +16,7 @@
 #
 import sys
 from contextlib import contextmanager
-from StringIO import StringIO
+from io import StringIO
 
 @contextmanager
 def captured_output():