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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 xstep(self):
 """The xstep of the baseline consensus class from which this class is derived is re-used to implement the xstep of the modified algorithm by replacing ``self.ZSf``, which is constant in the baseline algorithm, with a quantity derived from the additional variables ``self.Y1`` and ``self.U1``. It is also necessary to set the penalty parameter to unity for the duration of the x step. """


        self.YU1[:] = self.Y1 - self.U1
        self.ZSf = np.conj(self.Zf) * (self.Sf + sl.rfftn(
            self.YU1, None, self.cri.axisN))
        rho = self.rho
        self.rho = 1.0
        super(ConvCnstrMODMaskDcpl_Consensus, self).xstep()
        self.rho = rho