Exercise: Convert your script to module

• Take one of your real scripts (from work or from a previous assignment). Create a backup copy.
• Change the script so it can be import-ed as a module and then it won't automatically execute anything, but that it still works when executed as a script.
• Add a new function to it called self_test and in that function add a few test-cases to your code using 'assert'.
• Write another script that will load your real file as a module and will run the self_test.
• Let me know what are the dificulties!