I usually use pyenv to manage my Python
interpreters and obtain them in whatever version I need. Another tool I
occasionally use is tox by Holger Krekel, which nicely
generates build matrices for library and python interpreter versions, that come
handy when you develop a library targeting multiple Python versions (and
dependencies).
However, until recently I didn't know how to use the two of them together.
With pyenv, I usually ended up with one python interpreter in my path, so
tox had only one interpreter to choose from, and I was missing out on tox'
selling point: testing your code over various versions of Python.
Install Multiple Python Version With Pyenv
Setting up your pyenv usually looks like this:
Now it is possible to use multiple Python versions here:
Then, tox can find interpreters, typically you will have a tox.ini in your
project that starts with something like this:
Invoking tox should now run tox with the two available Python versions, 2.7
and 3.5, skipping 3.4 unless it is installed.