how to use docopt examples

app.py

"""Usage:
    app.py --user=username --pwd=password --json
    app.py --user=username --pwd=password

Arguments:
    --user=username  Application User Name
    --pwd=password  Application password

Options:
    --json  enable json output
"""

#/usr/bin/python2.6 /home/sulla/PycharmProjects/testProj/app.py --user=shafi --pwd=testing --json

# Docopt is a library for parsing command line arguments
import docopt
import json

if __name__ == '__main__':

    result = {}

    try:
        # Parse arguments, use file docstring as a parameter definition
        arguments = docopt.docopt(__doc__)

        user = arguments['--user']
        pwd = arguments['--pwd']

        result['user'] = user
        result['pwd'] = pwd
        result['result'] = 'ok'

        if arguments['--json']:
            print json.dumps(result,indent=4)

    # Handle invalid options
    except docopt.DocoptExit as e:
        print e.usage