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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 lifter(cepstra, L=22):
 """Apply a cepstral lifter the the matrix of cepstra. This has the effect of increasing the magnitude of the high frequency DCT coeffs. :param cepstra: the matrix of mel-cepstra, will be numframes * numcep in size. :param L: the liftering coefficient to use. Default is 22. L <= 0 disables lifter. """

    if L > 0:
        nframes,ncoeff = numpy.shape(cepstra)
        n = numpy.arange(ncoeff)
        lift = 1 + (L/2.)*numpy.sin(numpy.pi*n/L)
        return lift*cepstra
    else:
        # values of L <= 0, do nothing
        return cepstra