We have several techniques to install a Python module or package:

• We can write setup.py and use the distribution utilities module, distutils, to install the package into Python's lib/site-packages directory. This is described in detail in the Python Packaging Authority documentation. See https://tox.readthedocs.io/en/latest/ for more information.
• We can set the PYTHONPATH environment variable to include our packages and modules. We can set this temporarily in a shell, or we can set it more permanently by editing our ~/.bash_profile or the system's /etc/profile. We'll take a look at this later in...