Switching between python versions using virtualenvwrapper on Mac OS

Question

I am trying to figure out how to switch between different Python versions on my Mac using virtualenvwrapper package.

My Mac came with Python2.7 and I've installed the latest version (Python3.7). I have figured out how to make an environment with Python3.7 using the following:

mkvirtualenv -p /usr/local/bin/python3 p3

But when I check PYTHONPATH, VIRTUALENVWRAPPER_PYTHON, and VIRTUALENV_PYTHON, they all point to the original Python 2.7.

How do I know that the environment I created is actually running Python3?

I am new to virtual environments and the Mac world, so this has all be a bit confusing to figure out. I appreciate any input.

Answer 1

Do this:

python3.6 -m virtualenv /path/to/your/venv

This will guarantee your virtualenv to install for that specific python version.

If you are not sure where your python executable is, fire up a python console:

>>> import sys
>>> print(sys.executable)
/full/path/to/your/python/executable

You'll usually find other python versions lying there - usually they're symlinked to your /usr/local/bin/ which will make you able to call them by name , e.g. python3.6