Nil is an empty UUID.
var Nil = nilUUID
A UUID is a 128 bit (16 byte) Universal Unique Identifier as defined in RFC 4122.
type UUID [16]byte
func MustUUID() UUID
MustUUID generates new unique UUID on failure panics.
func NewUUID() (UUID, error)
NewUUID generates new uuid.
func (u UUID) String() string