python environments

Python virtual environments and pip

Python versions

which python

which python3

python --version

python3 --version

Virtual environments in Python 2

virtualenv env-py2

source env-py2/bin/activate

(note change in prompt)

Virtual environments in Python 3

python3 -m venv env-py3

official documentation

Installing from the Python Package Index (pypi)

See https://docs.python.org/3/tutorial/venv.html

Then see, for example python-ofcourse or git by a bus