def save(seq, fname, index, extension):
    """save audio sequences to file"""
    output = np.hstack(seq)
    file_name = fname.parent / (fname.stem + f"_{index:04}{extension}")
    fname.parent.mkdir(exist_ok=True, parents=True)
    sf.write(file_name, output, samplerate=16000)
save audio sequences to file
utils/cut_by_vad.py