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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 logspec2s2mfc(logspec, ncep=13):
 """Convert log-power-spectrum bins to MFCC using the 'legacy' Sphinx transform"""

    nframes, nfilt = logspec.shape
    melcos = s2dctmat(nfilt, ncep, 1./nfilt)
    return numpy.dot(logspec, melcos.T) / nfilt