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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_Z(self,Y):
 """ Creates design matrix holding the lagged variables Parameters Y : np.array The dependent variables Y Returns The design matrix Z """


        Z = np.ones(((self.ylen*self.lags +1),Y[0].shape[0]))
        return self.create_design_matrix(Z, self.data, Y.shape[0], self.lags)