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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 fluid_synth_write_s16_stereo(synth, len):
 """Return generated samples in stereo 16-bit format. Return value is a Numpy array of samples. """

    import numpy
    buf = create_string_buffer(len * 4)
    fluid_synth_write_s16(synth, len, buf, 0, 2, buf, 1, 2)
    return numpy.fromstring(buf[:], dtype=numpy.int16)