language: python
python:
  # - "2.7"
  # - "3.4"
  - "3.5"
  - "3.5-dev" # 3.5 development branch
  - "3.6"
  - "3.6-dev" # 3.6 development branch
  - "3.7-dev" # 3.7 development branch
  - "3.7"
  - "nightly" # currently points to 3.7-dev
  # command to install dependencies.
install:
  - sudo apt-get install python-matplotlib
  - pip install sphinx
  - python setup.py install
  - pip install coveralls
script: 
  - python -m unittest discover
  - coverage run --source . -m unittest discover
after_success: coveralls

language: python
matrix:
  include:
  - python: "3.5"
  - python: "3.5-dev" # 3.5 development branch
  - python: "3.6"
  - python: "3.6-dev" # 3.6 development branch
  - python: "3.7-dev" # 3.7 development branch
  - python: "3.7"
    dist: xenial
    sudo: true
  - python: "nightly" # currently points to 3.7-dev
  # command to install dependencies.
install:
  - sudo apt-get install python-matplotlib
  - pip install sphinx
  - python setup.py install
  - pip install coveralls
script: 
  - python -m unittest discover
  - coverage run --source . -m unittest discover
after_success: coveralls

Use matrix config to support python 3.7
Use matrix config to support python 3.7
