If you have an Arista Networks switch, here's a little easter egg that you may find amusing. At the command prompt type show chickens. You will get the following output:
The history behind it is interesting. It began with a discussion between some of the Arista SW people about the usefulness of a command. Someone commented, "Well, what does show chickens do, a chicken?" (The command in question was less than ideal because the output contained no useful information) The answer given was "No, it shows a donkey".
You can also do "show donkeys" or "show farm" to show them both. The Arista CLI is implemented using Python. The DonkeyCli.py file is just one piece. It is more or less there to give Arista customers an idea of how to implement custom CLI commands. Try "cat /usr/lib/python2.7/site-packages/CliPlugin/DonkeyCli.py" to look at it.