class HelloActor(Actor):
    def setup_parser(self, parser):
        parser.add_argument('--hello', action='store', type=str)

    def __call__(self, hello):
        self.info(hello)
        return 0

class Program:
    def main(self, argv):
        # Create argument parser.
        parser = argparse.ArgumentParser()

        CommandParser('Example Commands')([
            Command('hello', 'Print hello message', HelloActor()),
        ]).setup_parser(parser)

        # Create the runner object.
        runner = Runner('my-cli', parser).setup_parser()

        # Parse arguments - the runner internally process its own arguments
        # that were setup by previous call to `setup_parser()`.
        args = runner.parse_args(argv)

        # You can handle your own global arguments here.

        # Now we setup the default logger - it produces output to stdout
        # and stderr.
        runner.default_logger()

        # And finally, we execute the requested command and return its exit
        # code.
        return runner.execute(args)


if __name__ == "__main__":
    program = Program()
    sys.exit(program.main(sys.argv[1:]))