Simple Example

Suppose to make a following trivial greeting command consists of two subcommands supplied as functions shown below.

"""Sample command of dsargparse package.

This text will be used as description of this command.
"""
def greeting(title, name): # pylint: disable=unused-argument
    """Print a greeting message.

    This command print "Good morning, <title> <name>.".

    Args:
      title: title of the person.
      name: name of the person.
    """
    print("Good morning, {title} {name}.".format(**locals()))
    return 0


def goodbye(name): # pylint: disable=unused-argument
    """Print a goodbye message.

    This command print "Goodbye, <name>.".

    Args:
      name: name of the person say goodbye to.
    """
    print("Goodbye, {name}".format(**locals()))
    return 0

The dsargparse reduces codes you need from the before

# Before dsargparse
import sys
import textwrap

import argparse

def main():
    """ The main function.
    """
    parser = argparse.ArgumentParser(
      description=textwrap.dedent("""\
        Sample command of argparse package.

        This text will be used as description of this command.
        """))
    subparsers = parser.add_subparsers()

    greeting_cmd = subparsers.add_parser(
        "greeting",
        help="Print a greeting message.",
        description=textwrap.dedent("""\
            Print a greeting message.

            This command print "Good morning, <title> <name>".
            """))
    greeting_cmd.add_argument(
        "title", help="title of the person say greetings to")
    greeting_cmd.add_argument(
        "name", help="name of the person say greetings to.")
    greeting_cmd.set_defaults(cmd=greeting)

    goodbye_cmd = subparsers.add_parser(
        "goodbye",
        help="Print a goodbye message.",
        description=textwrap.dedent("""\
            Print a goodbye message.

            This command print "Goodbye, <name>".
            """))
    goodbye_cmd.add_argument(
        "name", help="name of the person say goodbye to.")
    goodbye_cmd.set_defaults(cmd=goodbye)

    args = parser.parse_args()
    return args.cmd(**args)


if __name__ == "__main__":
    sys.exit(main())

to the after

# After dsargparse
import sys

import dsargparse

def main():
    """ The main function.
    """
    parser = dsargparse.ArgumentParser(main=main)
    subparsers = parser.add_subparsers()

    greeting_cmd = subparsers.add_parser(greeting)
    greeting_cmd.add_argument("title")
    greeting_cmd.add_argument("name")

    goodbye_cmd = subparsers.add_parser(goodbye)
    goodbye_cmd.add_argument("name")

    return parser.parse_and_run()


if __name__ == "__main__":
    sys.exit(main())