Argparse is fantastic. I recently had to shift some code from taking input from a csv to taking input from command line and I was dreading how much coding it'd involve. It took me 5 minutes of googling to come across argparse and another minute to find my exact use case written out in 5 lines of code.

The kicker is that once you define it and let it capture inputs, it outputs absolutely standard professional level error messages for bad parameters. I did not have to write any exception handling code at all. I could not believe that what I thought would take me several days was done in less than an hour.