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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_standard_dev(self, rup, imt, C):
 """ Compute the the standard deviation in terms of magnitude described on p. 1866, eq. 6 """

        sigma_mean = 0.
        if rup.mag <= 7.0:
            sigma_mean = (C['c12'] * rup.mag) + C['c13']
        elif rup.mag > 7.0:
            sigma_mean = (-0.00695 * rup.mag) + C['c14']
        return sigma_mean