code: def dawn_utc(self, date, latitude, longitude, depression=0, observer_elevation=0):
          
  
          if depression == 0:
              depression = self._depression
          depression += 90
  
          try:
              return self._calc_time(depression, SUN_RISING, date, latitude, longitude, observer_elevation)
          except ValueError as exc:
              if exc.args[0] == "math domain error":
                  raise AstralError(
                      (
                          "Sun never reaches %d degrees below the horizon, "
                          "at this location."
                      )
                      % (depression - 90)
                  )
              else:
                  raise
docs: Calculate dawn time in the UTC timezone.
  
          :param date:       Date to calculate for.
          :type date:        :class:`datetime.date`
          :param latitude:   Latitude - Northern latitudes should be positive
          :type latitude:    float
          :param longitude:  Longitude - Eastern longitudes should be positive
          :type longitude:   float
          :param depression: Override the depression used
          :type depression:  float
          :param observer_elevation:  Elevation in metres to calculate dawn for
          :type observer_elevation:   int
  
          :return: The UTC date and time at which dawn occurs.
          :rtype: :class:`~datetime.datetime`