How can I print a Python file's docstring when executing it?

Question

I have a Python script with a docstring. When the parsing of the command-line arguments does not succeed, I want to print the docstring for the user\'s information.

Answer 1

Here is an alternative that does not hardcode the script's filename, but instead uses sys.argv[0] to print it. Using %(scriptName)s instead of %s improves readability of the code.

#!/usr/bin/env python
"""
Usage: %(scriptName)s

This describes the script.
"""

import sys
if len(sys.argv) < 2:
   print __doc__ % {'scriptName' : sys.argv[0].split("/")[-1]}
   sys.exit(0)