code: func (g *rfc4122Generator) NewV1() (UUID, error) {
  	u := UUID{}
  
  	timeNow, clockSeq, err := g.getClockSequence()
  	if err != nil {
  		return Nil, err
  	}
  	binary.BigEndian.PutUint32(u[0:], uint32(timeNow))
  	binary.BigEndian.PutUint16(u[4:], uint16(timeNow>>32))
  	binary.BigEndian.PutUint16(u[6:], uint16(timeNow>>48))
  	binary.BigEndian.PutUint16(u[8:], clockSeq)
  
  	hardwareAddr, err := g.getHardwareAddr()
  	if err != nil {
  		return Nil, err
  	}
  	copy(u[10:], hardwareAddr)
  
  	u.SetVersion(V1)
  	u.SetVariant(VariantRFC4122)
  
  	return u, nil
  }
docs: // NewV1 returns UUID based on current timestamp and MAC address.