How to save i2s audio data to SD-CARD.

I’m trying to save i2s audio data to SD-CARD with Maixduino.

Could you please any infomation to save…

I already success to record and play immidiatry below this code.

-- a part of source code --
while True:
    audio = rx.record(256)
    audio_data = audio.to_bytes()
    play_audio = Audio(audio_data)
    tx.play(play_audio)
--