Actually this isn’t as simple as this… you own the copyright and must explain in what conditions you made this available and what people can expect. That’s what a license is for. In most of Europe the concept of public domain that exists in other countries doesn’t apply in the same way. My suggestion is to use one of the know open source licenses.
Perhaps you can have a look at this other thread:
Most of the discussion there applies here.
For the license I would consider something simple like MIT or Free Public License
You can use that code as an example for command line parameters in you code.
With only two parameters for the command line, you can probably get away with something simpler.
Here are a couple of references for command line parsing in python:
Python 3 - Command Line Arguments - Tutorialspoint
Python Command Line Arguments – Real Python
Looks like it… anything related to managing requirements/environments should give you some good background.