[tox]
envlist = docs
skipsdist = true

[testenv:docs]
deps =
    sphinx
    sphinx_rtd_theme
basepython = python2.7
commands =
    sphinx-build -W -b html -d {envtmpdir}/doctrees docs docs/_build/html

[tox]
envlist = docs
skipsdist = true

[testenv:docs]
deps =
    sphinx
    sphinx_rtd_theme
basepython = python3
commands =
    sphinx-build -W -b html -d {envtmpdir}/doctrees docs docs/_build/html

Upgrade to python3 for docs rendering
Upgrade to python3 for docs rendering
