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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 coupl_model8(self):
 """ Variant of toggle switch. """

        self.Coupl = 0.5*self.Adj_signed
        # reduce the value of the coupling of the repressing genes
        # otherwise completely unstable solutions are obtained
        for x in np.nditer(self.Coupl,op_flags=['readwrite']):
            if x < -1e-6:
                x[...] = -0.2