code: def _get_stddevs(self, C, C_PGA, pga1100, rup, sites, stddev_types):
          
          std_intra = self._compute_intra_event_std(C, C_PGA, pga1100, rup.mag,
                                                    sites.vs30,
                                                    sites.vs30measured)
          std_inter = self._compute_inter_event_std(C, C_PGA, pga1100, rup.mag,
                                                    sites.vs30)
          stddevs = []
          for stddev_type in stddev_types:
              assert stddev_type in self.DEFINED_FOR_STANDARD_DEVIATION_TYPES
              if stddev_type == const.StdDev.TOTAL:
                  stddevs.append(np.sqrt(std_intra ** 2 + std_inter ** 2))
              elif stddev_type == const.StdDev.INTRA_EVENT:
                  stddevs.append(std_intra)
              elif stddev_type == const.StdDev.INTER_EVENT:
                  stddevs.append(std_inter)
          return stddevs
docs: Return standard deviations as described in paragraph 'Equations for
          standard deviation', page 81.