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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 sg_summary_audio(tensor, sample_rate=16000, prefix=None, name=None):
 r"""Register `tensor` to summary report as audio Args: tensor: A `Tensor` to log as audio sample_rate : An int. Sample rate to report. Default is 16000. prefix: A `string`. A prefix to display in the tensor board web UI. name: A `string`. A name to display in the tensor board web UI. Returns: None """

    # defaults
    prefix = '' if prefix is None else prefix + '/'
    # summary name
    name = prefix + _pretty_name(tensor) if name is None else prefix + name
    # summary statistics
    if not tf.get_variable_scope().reuse:
        tf.summary.audio(name + '-au', tensor, sample_rate)