code: func getGlobalRand() (*Locking, *rand.Rand) {
  	globalOnce.Do(func() {
  		globalRandBase = newRand()
  		globalRand = &Locking{R: wrapped{globalRandBase}}
  	})
  	return globalRand, globalRandBase
  }
docs: // getGlobalRand returns globalRand and its Locking wrapper. This must be used
  // instead of direct variable access in order to ensure that everything is
  // initialized.
  //
  // We use a Once to perform this initialization so that we can enable
  // applications to set the seed via rand.Seed if they wish.