code: def write_skycatalog(self,filename):
          
          if self.all_radec is None:
              return
          ralist = self.all_radec[0]#.tolist()
          declist = self.all_radec[1]#.tolist()
          f = open(filename,'w')
          f.write("#Sky positions for: "+self.name+'\n')
          f.write("#RA        Dec\n")
          f.write("#(deg)     (deg)\n")
          for i in range(len(ralist)):
              f.write('%0.12f  %0.12f\n'%(ralist[i],declist[i]))
          f.close()
docs: Write out the all_radec catalog for this image to a file.