diff --git a/tests/test_replay_attack.py b/tests/test_replay_attack.py
index aba4b227..6251c8c5 100755
--- a/tests/test_replay_attack.py
+++ b/tests/test_replay_attack.py
@@ -59,7 +59,8 @@
 import tuf.client.updater as updater
 import tuf.repository_tool as repo_tool
 import tuf.unittest_toolbox as unittest_toolbox
-import tuf._vendor.six as six
+
+import six
 
 # The repository tool is imported and logs console messages by default.  Disable
 # console log messages generated by this unit test.