Interpret command line arguments.

    :param args: `sys.argv`
    :return: The populated argparse namespace.

def _parse_args(args):
    """
    Interpret command line arguments.

    :param args: `sys.argv`
    :return: The populated argparse namespace.
    """

    parser = argparse.ArgumentParser(prog='nibble',
                                     description='Speed, distance and time '
                                                 'calculations around '
                                                 'quantities of digital '
                                                 'information.')
    parser.add_argument('-V', '--version',
                        action='version',
                        version='%(prog)s ' + nibble.__version__)
    parser.add_argument('-v', '--verbosity',
                        help='increase output verbosity',
                        action='count',
                        default=0)
    parser.add_argument('expression',
                        type=util.decode_cli_arg,
                        nargs='+',
                        help='the calculation to execute')
    return parser.parse_args(args[1:])