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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 block_cat(self, Y0, Y1):
 """Concatenate components corresponding to Y0 and Y1 blocks into Y. """


        # Axes are swapped here for similar reasons to those
        # motivating swapping in cbpdn.ConvTwoBlockCnstrnt.block_cat
        Y1sa = np.swapaxes(Y1, self.cri.axisM, -1)[..., 0]

        # If cri.Cd > 1 (multi-channel dictionary) Y0 has a singleton
        # channel axis but Y1 has a non-singleton channel axis. To make
        # it possible to concatenate Y0 and Y1, we reshape Y1 by a
        # partial ravel of axisM and axisC onto axisM.
        if self.cri.Cd > 1:
            shp = list(Y1sa.shape)
            shp[self.cri.axisM] *= shp[self.cri.axisC]
            shp[self.cri.axisC] = 1
            Y1sa = Y1sa.reshape(shp)

        return np.concatenate((Y0, Y1sa), axis=self.cri.axisM)