code: func (hl *hashList) Encode(w io.Writer) error {
  	for file, h := range hl.hashes {
  		if _, err := fmt.Fprintf(w, "%x  %s\n", h.Sum([]byte{}), file); err != nil {
  			return err
  		}
  	}
  	return nil
  }
docs: // Encode takes the current sum of all the hashes and saves the hash list as a
  // SHA256SUMS-style text file.