code: func NewRandom() UUID {
  	if gu, err := guuid.NewRandom(); err == nil {
  		return UUID(gu[:])
  	}
  	return nil
  }
docs: // Random returns a Random (Version 4) UUID or panics.
  //
  // The strength of the UUIDs is based on the strength of the crypto/rand
  // package.
  //
  // A note about uniqueness derived from the UUID Wikipedia entry:
  //
  //  Randomly generated UUIDs have 122 random bits.  One's annual risk of being
  //  hit by a meteorite is estimated to be one chance in 17 billion, that
  //  means the probability is about 0.00000000006 (6 × 10−11),
  //  equivalent to the odds of creating a few tens of trillions of UUIDs in a
  //  year and having one duplicate.