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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_stddevs(self, sites, rup, C, stddev_types, ln_y_ref, exp1, exp2):
 """ Returns the standard deviation, which is fixed at 0.65 for every site """

        ret = []
        for stddev_type in stddev_types:
            assert stddev_type in self.DEFINED_FOR_STANDARD_DEVIATION_TYPES
            if stddev_type == const.StdDev.TOTAL:
                # eq. 13
                ret.append(0.65 * np.ones_like(sites.vs30))
        return ret