POX is another controller written in Python. It can also function as an SDN switch, or a network operating system. POX is very easy to install and test from the source.

POX requires Python 2.7 to run, and currently it does not support Python 3. This is documented in the POX wiki: https://openflow.stanford.edu/display/ONL/POX+Wiki#POXWiki-DoesPOXsupportPython3%3F. Python 2 is still the commonest version even in SDN emulators such as Mininet, and hence it is advisable to have it installed for these recipes.