code: func ChecksumVV(vv buffer.VectorisedView, initial uint16) uint16 {
  	var odd bool
  	sum := initial
  	for _, v := range vv.Views() {
  		if len(v) == 0 {
  			continue
  		}
  		s := uint32(sum)
  		if odd {
  			s += uint32(v[0])
  			v = v[1:]
  		}
  		odd = len(v)&1 != 0
  		sum = calculateChecksum(v, s)
  	}
  	return sum
  }
docs: // ChecksumVV calculates the checksum (as defined in RFC 1071) of the bytes in
  // the given VectorizedView.
  //
  // The initial checksum must have been computed on an even number of bytes.