Supervisor is a system that allows its users to monitor and control a number of processes. I've seen a lot of users utilize to automatically restart a process if it ever crashes/stops. For full details of what it is capable of visit the official documentation.
With the installation methods below, you can check your version of Supervisor with
Install from Ubuntu Package (recommended)
Installing through the ubuntu packages is somewhat safer and will probably safe you a lot of hassle with configuration files later.
sudo apt-get install supervisor
On Ubuntu 16.04 this should install version
Install through Pip
Installing through the python package management tool (pip) will give you the latest stable version.
Install Pip if you haven't already and then execute:
sudo pip install supervisor
You should get version