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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 stChromaFeaturesInit(nfft, fs):
 """ This function initializes the chroma matrices used in the calculation of the chroma features """

    freqs = numpy.array([((f + 1) * fs) / (2 * nfft) for f in range(nfft)])    
    Cp = 27.50    
    nChroma = numpy.round(12.0 * numpy.log2(freqs / Cp)).astype(int)

    nFreqsPerChroma = numpy.zeros((nChroma.shape[0], ))

    uChroma = numpy.unique(nChroma)
    for u in uChroma:
        idx = numpy.nonzero(nChroma == u)
        nFreqsPerChroma[idx] = idx[0].shape
    
    return nChroma, nFreqsPerChroma