install python in travis osx env

.travis.yml

@@ -1,3 +1,4 @@
+os: linux
 sudo: false
 language: python
 
@@ -28,6 +29,14 @@ matrix:
       env: TOXENV=py
   fast_finish: true
 
+before_install:
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then
+      brew update;
+      brew install python3 redis memcached;
+      virtualenv -p python3 ~/py-env;
+      . ~/py-env/bin/activate;
+    fi
+
 install:
   - pip install tox