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
Returns the standard deviation, which is fixed at 0.65 for every site