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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_anelastic_attenuation_term(self, C, rrup):
 """ Returns the anelastic attenuation term defined in equation 25 """

        f_atn = np.zeros(len(rrup))
        idx = rrup >= 80.0
        f_atn[idx] = (C["c20"] + C["Dc20"]) * (rrup[idx] - 80.0)
        return f_atn