code: func GetDevEUIsForMulticastGroup(db sqlx.Queryer, multicastGroupID uuid.UUID) ([]lorawan.EUI64, error) {
  	var out []lorawan.EUI64
  
  	err := sqlx.Select(db, &out, `
  		select
  			dev_eui
  		from
  			device_multicast_group
  		where
  			multicast_group_id = $1
  	`, multicastGroupID)
  	if err != nil {
  		return nil, handlePSQLError(err, "select error")
  	}
  
  	return out, nil
  }
docs: // GetDevEUIsForMulticastGroup returns all Device EUIs within the given
  // multicast-group id.