Return the parser object for this script.

def get_parser():
    """Return the parser object for this script."""
    from argparse import ArgumentParser, ArgumentDefaultsHelpFormatter
    parser = ArgumentParser(description=__doc__,
                            formatter_class=ArgumentDefaultsHelpFormatter)
    parser.add_argument("-n",
                        dest="n", default=10, type=int,
                        help="Show TOP-N results")
    parser.add_argument("--port",
                        dest="port", default=5000, type=int,
                        help="where should the webserver run")
    parser.add_argument("--use_segmenter",
                        dest="use_segmenter",
                        default=False,
                        action='store_true',
                        help=("try to segment the input for multiple symbol "
                              "recognition"))
    return parser