dist: xenial
language: python
cache: pip
python:
  - 2.7.13
  - 3.4
  - 3.5
  - 3.6
  - 3.7
install:
  - pip install tox-travis
script:
  - tox

dist: bionic
language: python
cache: pip
python:
  - 2.7.17
  # - 3.4 not existing on bionic
  - 3.5
  - 3.6
  - 3.7
  - 3.8
install:
  - pip install tox-travis
script:
  - tox

Extend Travis conf to python 3.8 (but python 3.4 won't be tested anymore).
Extend Travis conf to python 3.8 (but python 3.4 won't be tested anymore).
