Translate non-ASCII characters to spaces or equivalent ASCII characters

def clean_csvs(dialogpath=None):
    """ Translate non-ASCII characters to spaces or equivalent ASCII characters """
    dialogdir = os.dirname(dialogpath) if os.path.isfile(dialogpath) else dialogpath
    filenames = [dialogpath.split(os.path.sep)[-1]] if os.path.isfile(dialogpath) else os.listdir(dialogpath)
    for filename in filenames:
        filepath = os.path.join(dialogdir, filename)
        df = clean_df(filepath)
        df.to_csv(filepath, header=None)
    return filenames