optparse - Command line option parser

(examples taken from LibRef)

from optparse import OptionParser
[...]
parser = OptionParser()
parser.add_option("-f", "--file", dest="filename",
                  help="write report to FILE", metavar="FILE")
parser.add_option("-q", "--quiet",
                  action="store_false", dest="verbose", default=True,
                  help="don't print status messages to stdout")

(options, args) = parser.parse_args()

# if user typed <yourscript> --file=outfile -q:
options.filename    # "outfile"
options.verbose     # False

# if user types <yourscript> without options:
options.filename    # None
options.verbose     # True

optparse is flexible in handling options, thus all of these will be equivalent:

<yourscript> -f outfile --quiet
<yourscript> --quiet --file outfile
<yourscript> -q -foutfile
<yourscript> -qfoutfile

optparse will automatically create the help listing for your options:

usage: <yourscript> [options]

options:
  -h, --help            show this help message and exit
  -f FILE, --file=FILE  write report to FILE
  -q, --quiet           don't print status messages to stdout