def setup_parser(parser):
    """
    Setup argument parser.
    :param parser: argument parser
    :return: configured parser
    """
    parser.add_argument('--chunksize', type=int, required=False,
                        help="Use chunking for large files. N as size of chunk.")
    parser.add_argument('--samplesize', type=int, required=False,
                        help="Use sampling. N as first rows read")
    return parser