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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 incremental_value(self, slip_moment, mmax, mag_value, bbar, dbar):
 """ Returns the incremental rate with Mmax = Mag_value """

        delta_m = mmax - mag_value
        a_3 = self._get_a3(bbar, dbar, slip_moment, mmax)
        return a_3 * bbar * (np.exp(bbar * delta_m) - 1.0) * (delta_m > 0.0)