Always use virtual environment to ensure we all use the same Python version (Python 3), packages, etc.
To set up the virtual environment:
./setup.sh
From now on just activate the environment using source bin/activate and deactivate using deactivate.
Use pip3 install pkgname to install new packages. Remember to update requirements.txt, preferably by running:
pip3 freeze > requirements.txt
and ensure (probably applies to Ubuntu users only) that requirements.txt does not contain the flawed pkg-resources==0.0.0 dependency (remove the line if necessary).
In order to be able to test the code without being connected to the brick, we have the TEST environment which does not use the true ev3dev libraries but replaces them by an abstraction obtained here (infinite thanks to Timon Reinold!).
More info on how to run the code in the two environments will follow soon.