def csv_args(unix=False):
    """
    how to read and write csv file
    differs between windows and unix (mac+linux)

    Args:
        unix (bool): if it is a unix computer

    Returns:
        dict: arguments to read and write csv files
    """
    if unix:
        return dict(sep=',', decimal='.')
    else:
        return dict(sep=';', decimal=',')