Travis test

.travis.yml

diff --git a/.travis.yml b/.travis.yml
index 3523d22..3c3a9ff 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -26,6 +26,8 @@
     - sudo apt-get install swig
     - sudo apt-get install google-perftools
     - sudo apt-get install libgoogle-perftools-dev
+    - sudo add-apt-repository ppa:jonathonf/python-3.6 -y
+    - sudo apt-get update -q
     - sudo apt-get install python3.6
     - sudo apt-get install python3.6-dev
     - eval "${MATRIX_EVAL}"