To start the server you need to run: python ./server.py
And that's fine.
However, after either hitting Cltr-C or making process run in the background somehow there is no actual way to control the behaviour of the server - you cannot safely stop it, what causes the network socket to get broken thus we end up with broken pipe and blocked port on the NIC which we were listening on.
Thus, as a users, we want to submit simple command to the server
when the server is running
to properly control server's behaviour.

As for now, the commands' set is defined using const variable on top of server.py file.
It is kind of fine until you actually need to add support for a command to a server. Such solution creates a coupling between the server.py and commands as they are inside directory of commands.
We don't want the core server file to rely on implementation of any protocol.
So, the issue is to redesign commands mechanism to use "modules" mechanism to load commands as a module.
So, the default protocol for the server is Q.U.O.Y Protocol which defines just 4 or 5 basic commands of my own, custom purpose.
However, if we would like to implement some other custom protocol or even a HTTP protocol we would need to refactor some parts of server.py file.
Start defining that commands set is a module now - a file in commands directories.
Thus, we load it as a module, but the server needs to know that it should be used as a mapping for commands whereas all the commands cannot be inside one file. Those commands shall be placed in the subdirectory of commands with protocol name.

There is no option for an administrator of server to remove arbitrary user session or in other words: to halt the session.
In other words, we need to add a command which will allow to stop user's session just by using simple, CLI command using UNIX socket.