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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 dct2(input, K=13):
 """Convert log-power-spectrum to MFCC using the normalized DCT-II"""

    nframes, N = input.shape
    freqstep = numpy.pi / N
    cosmat = dctmat(N,K,freqstep,False)
    return numpy.dot(input, cosmat) * (2.0 / N)