大佬可以解释下这几行代码的意思吗

[ylrh333]

ct = CzscAdvancedTrader(bg, get_signals)
    last_dt = {signal.key: ct.end_dt for signal in signals}

    for bar in tqdm(bars_right, desc=f'generate snapshots of {bg.symbol}'):
        ct.update(bar)

        for signal in signals:
            html_path = os.path.join(home_path, signal.key)
            os.makedirs(html_path, exist_ok=True)
            if bar.dt - last_dt[signal.key] > timedelta(days=5) and signal.is_match(ct.s):   #尤其是这句话。
                file_html = f"{bar.symbol}_{signal.key}_{ct.s[signal.key]}_{bar.dt.strftime('%Y%m%d_%H%M')}.html"
                file_html = os.path.join(html_path, file_html)
                print(file_html)
                ct.take_snapshot(file_html)
                last_dt[signal.key] = bar.dt