code: func Bytes(m []ValidMessage) [][]byte {
  	ret := make([][]byte, len(m))
  	//copy because we don't want to hold references to m's fragments
  	for i, f := range m {
  		ret[i] = make([]byte, len(f))
  		copy(ret[i], []byte(f))
  	}
  	return ret
  }
docs: // Bytes will turn a slice of valid messages into a slice of byte slices