diff --git a/.travis.yml b/.travis.yml
index 1d5d69f3..e37dbcf1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,5 +7,7 @@ before_install:
 install:
     - sudo cpanm Test::Differences Test::TrailingSpace
     - "`which python3` -m pip install --user flake8"
+    - "`which python3` -m pip install --user six"
+    - "`which python` -m pip install --user six"
     - which python
 script: "sh -x scripts/travis-ci-build"