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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 append_data(self, data_buffer):
 """ Append data to this audio stream :Parameters: `data_buffer` : str, basestring, Bytes a buffer with a length multiple of (sample_width * channels) """


        if len(data_buffer) % (self.sample_width * self.channels) != 0:
            raise ValueError("length of data_buffer must be a multiple of (sample_width * channels)")

        self._buffer += data_buffer
        self._left += len(data_buffer)