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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 _get_distance_scaling_term(self, C, rval, mag):
 """ Returns the distance scaling term of the GMPE described in equation 2 """

        r_adj = np.sqrt(rval ** 2.0 + C["h"] ** 2.0)
        return (
            (C["c1"] + C["c2"] * (mag - self.CONSTS["Mref"])) *
            np.log10(r_adj / self.CONSTS["Rref"]) -
            (C["c3"] * (r_adj - self.CONSTS["Rref"])))