def METHOD_NAME(args):
    '''Parse command line
    This function writes to stdout/stderr and may call `system.exit()` instead
    of throwing an exception if it encounters errors.
    '''
    parser = ArgumentParser(
        description=textwrap.dedent(
            '''\
        Unmounts an S3QL file system. The command returns only after all data
        has been uploaded to the backend.'''
        )
    )
    parser.add_log()
    parser.add_debug()
    parser.add_quiet()
    parser.add_version()
    parser.add_argument(
        "mountpoint",
        metavar='<mountpoint>',
        type=(lambda x: x.rstrip('/')),
        help='Mount point to un-mount',
    )
    parser.add_argument(
        '--lazy',
        "-z",
        action="store_true",
        default=False,
        help="Lazy umount. Detaches the file system immediately, even if there "
        'are still open files. The data will be uploaded in the background '
        'once all open files have been closed.',
    )
    return parser.METHOD_NAME(args)