code: func (hash Hash) String() string {
  	for i := 0; i < HashSize/2; i++ {
  		hash[i], hash[HashSize-1-i] = hash[HashSize-1-i], hash[i]
  	}
  	return hex.EncodeToString(hash[:])
  }
docs: // String returns the Hash as the hexadecimal string of the byte-reversed
  // hash.