machine:
  python:
    version: 2.7.11
checkout:
  post:
    - git submodule init
    - git submodule update
dependencies:
  post:
    - pip install beautifulsoup4 requests websocket-client coverage pytest phonenumbers flake8 regex==2015.11.22 termcolor --upgrade
test:
  override:
    - flake8 ./
    - python -W default::Warning -m pytest test

machine:
  python:
    version: 2.7.10
checkout:
  post:
    - git submodule init
    - git submodule update
dependencies:
  post:
    - pip install beautifulsoup4 requests websocket-client coverage pytest phonenumbers flake8 regex==2015.11.22 termcolor --upgrade
test:
  override:
    - flake8 ./
    - python -W default::Warning -m pytest test

Switch Circle to use Python 2.7.10
Switch Circle to use Python 2.7.10

2.7.10 is the latest available on 12.04 builds.