code: def make_header(self):
          
          cards = [fits.Card("TELESCOP", "GLAST"),
                   fits.Card("INSTRUME", "LAT"),
                   fits.Card(self._conv.coordsys, self._coordsys),
                   fits.Card("PIXTYPE", "HEALPIX"),
                   fits.Card("ORDERING", self.ordering),
                   fits.Card("ORDER", self._order),
                   fits.Card("NSIDE", self._nside),
                   fits.Card("FIRSTPIX", 0),
                   fits.Card("LASTPIX", self._maxpix - 1),
                   fits.Card("HPX_CONV", self._conv.convname)]
  
          if self._coordsys == "CEL":
              cards.append(fits.Card("EQUINOX", 2000.0,
                                     "Equinox of RA & DEC specifications"))
  
          if self._region is not None:
              cards.append(fits.Card("HPX_REG", self._region))
              cards.append(fits.Card("INDXSCHM", "PARTIAL"))
          elif self._ipix is not None:
              cards.append(fits.Card("INDXSCHM", "EXPLICIT"))        
          else:
              if self._conv.convname in ['FGST_SRCMAP_SPARSE']:
                  cards.append(fits.Card("INDXSCHM", "SPARSE"))
              else:
                  cards.append(fits.Card("INDXSCHM", "IMPLICIT"))
  
          header = fits.Header(cards)
          return header
docs: Builds and returns FITS header for this HEALPix map