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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 _serve_audio_metadata(self, request):
 """Given a tag and list of runs, serve a list of metadata for audio. Note that the actual audio data are not sent; instead, we respond with URLs to the audio. The frontend should treat these URLs as opaque and should not try to parse information about them or generate them itself, as the format may change. Args: request: A werkzeug.wrappers.Request object. Returns: A werkzeug.Response application. """

    tag = request.args.get('tag')
    run = request.args.get('run')
    sample = int(request.args.get('sample', 0))

    events = self._multiplexer.Tensors(run, tag)
    response = self._audio_response_for_run(events, run, tag, sample)
    return http_util.Respond(request, response, 'application/json')