def METHOD_NAME(self, path, ref_len=None):
    wav, sr = sf.read(path)
    if wav.ndim == 2:
        wav = wav.mean(-1)
    assert wav.ndim == 1, wav.ndim
    assert sr == self.sample_rate, sr
    if ref_len is not None and abs(ref_len - len(wav)) > 160:
        print(f"ref {ref_len} != read {len(wav)} ({path})")
    return wav