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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 _compute_mean(self, C, A1, A2, A3, A4, A5, A6, mag, hypo_depth, rrup, mean, idx):
 """ Compute mean for subduction interface events, as explained in table 2, page 67. """

        mean[idx] = (A1 + A2 * mag + C['C1'] + C['C2'] * (A3 - mag) ** 3 +
                     C['C3'] * np.log(rrup[idx] + A4 * np.exp(A5 * mag)) +
                     A6 * hypo_depth)