diff --git a/.travis.yml b/.travis.yml
index 4f8dbb1..c1558f3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,10 +1,17 @@
 sudo: true
 dist: xenial
 language: python
-python:
-  - "3.6"
 install: pip install tox-travis
-env:
-  - ENV=pep8
+matrix:
+  include:
+    - name: "Python 3.5"
+      python: 3.5
+      env: ENV=pep8,py3
+    - name: "Python 3.6"
+      python: 3.6
+      env: ENV=pep8,py3
+    - name: "Python 3.7"
+      python: 3.7
+      env: ENV=pep8,py3
 script:
-  - tox -c tox.ini -e $ENV
\ No newline at end of file
+  - tox -c tox.ini -e $ENV
diff --git a/zaza/openstack/charm_tests/test_utils.py b/zaza/openstack/charm_tests/test_utils.py
index 30fba45..9cf2f59 100644
--- a/zaza/openstack/charm_tests/test_utils.py
+++ b/zaza/openstack/charm_tests/test_utils.py
@@ -168,7 +168,8 @@ class OpenStackBaseTest(unittest.TestCase):
         model.block_until_all_units_idle()
 
     def restart_on_changed(self, config_file, default_config, alternate_config,
-                           default_entry, alternate_entry, services, pgrep_full=False):
+                           default_entry, alternate_entry, services,
+                           pgrep_full=False):
         """Run restart on change tests.
 
         Test that changing config results in config file being updates and