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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 _create_dct_matrix(self):
 """ Create the not-quite-DCT matrix as used by Sphinx, and store it in ```self.s2dct```. """

        self.s2dct = numpy.zeros((self.mfcc_size, self.filter_bank_size))
        for i in range(0, self.mfcc_size):
            freq = numpy.pi * float(i) / self.filter_bank_size
            self.s2dct[i] = numpy.cos(freq * numpy.arange(0.5, 0.5 + self.filter_bank_size, 1.0, 'float64'))
        self.s2dct[:, 0] *= 0.5
        self.s2dct = self.s2dct.transpose()