Use Python 3 for docs
@@ -23,7 +23,7 @@ commands =
lint: python -m flake8 {posargs} {[_lint]files}
[testenv:docs]
-basepython = python2.7
+basepython = python3.9
deps = sphinx
commands = sphinx-build -W -q -b html docs {envtmpdir}/html {posargs}
