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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 read_wav(self, filename):
 """Read sample data for this sample from a WAV file. :param filename: the file from which to read """

        wave_input = None

        try:
            wave_input = wave.open(filename, 'r')
            wave_frames = bytearray(
                wave_input.readframes(wave_input.getnframes()))

            self.sample_data = [x >> 4 for x in wave_frames]

        finally:
            if wave_input is not None:
                wave_input.close()