dist: xenial
language: python
python:
  - "2.7"
  - "3.4"
  - "3.5"
  - "3.6"
  - "3.7"
  - "3.8"
  - "3.9-dev"
  - "pypy2.7-6.0"
  - "pypy3.5-6.0"
install: pip install tox-travis
script:
  - tox