code: def _make_input_file_list(binnedfile, num_files):
      
      outdir_base = os.path.abspath(os.path.dirname(binnedfile))
      outbasename = os.path.basename(binnedfile)
      filelist = ""
      for i in range(num_files):
          split_key = "%06i" % i
          output_dir = os.path.join(outdir_base, split_key)
          filepath = os.path.join(output_dir,
                                  outbasename.replace('.fits', '_%s.fits' % split_key))
          filelist += ' %s' % filepath
      return filelist
docs: Make the list of input files for a particular energy bin X psf type