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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def audio(audio, sample_rate, name=None, out=None, subdir='', timeout=5, **kwargs):
 """summary audio files to listen on a browser. An sampled array is converted as WAV audio file, saved to output directory, and reported to the ChainerUI server. The audio file is saved every called this function. The audio file will be listened on `assets` endpoint vertically. If need to aggregate audio files in row, use :func:`~chainerui.summary.reporter`. Example of how to set arguments:: Add description about the audio file:: Args: audio (:class:`numpy.ndarray` or :class:`cupy.ndarray` or \ :class:`chainer.Variable`):
 sampled wave array. sample_rate (int):
 sampling rate. name (str):
 name of image. set as column name. when not setting, assigned ``'audio'``. out (str):
 directory path of output. subdir (str):
 sub-directory path of output. **kwargs (dict):
 key-value pair to show as description. regardless of empty or not, timestamp on created the image is added. """


    from chainerui.report.audio_report import check_available
    if not check_available():
        return
    from chainerui.report.audio_report import report as _audio

    out_root = _chainerui_asset_observer.get_outpath(out)
    out_path = os.path.join(out_root, subdir)
    if not os.path.isdir(out_path):
        os.makedirs(out_path)
    col_name = name
    if col_name is None:
        col_name = 'audio'
    filename, created_at = _audio(audio, sample_rate, out_path, col_name)

    value = kwargs
    value['timestamp'] = created_at.isoformat()
    value['audios'] = {col_name: os.path.join(subdir, filename)}
    _chainerui_asset_observer.add(value)
    _chainerui_asset_observer.save(out_root, timeout)