def _load_table_data(table_file):
    """Load additional data from a csv table file.

    Args:
        table_file: Path to the csv file.

    Returns:
        header: a list of headers in the table.
        data: 2d array of data in the table.
    """
    with open(table_file, encoding="utf-8") as f:
        lines = f.readlines()
    header = lines[0].strip().split(",")
    data = [line.strip().split(",") for line in lines[1:]]
    return header, data