code: func generateID(l int) string {
  	const (
  		// ensures we backoff for less than 450ms total. Use the following to
  		// select new value, in units of 10ms:
  		// 	n*(n+1)/2 = d -> n^2 + n - 2d -> n = (sqrt(8d + 1) - 1)/2
  		maxretries = 9
  		backoff    = time.Millisecond * 10
  	)
  
  	var (
  		totalBackoff time.Duration
  		count        int
  		retries      int
  		size         = (l*5 + 7) / 8
  		u            = make([]byte, size)
  	)
  	// TODO: Include time component, counter component, random component
  
  	for {
  		// This should never block but the read may fail. Because of this,
  		// we just try to read the random number generator until we get
  		// something. This is a very rare condition but may happen.
  		b := time.Duration(retries) * backoff
  		time.Sleep(b)
  		totalBackoff += b
  
  		n, err := io.ReadFull(rand.Reader, u[count:])
  		if err != nil {
  			if retryOnError(err) && retries < maxretries {
  				count += n
  				retries++
  				logger.Errorf("error generating version 4 uuid, retrying: %v", err)
  				continue
  			}
  
  			// Any other errors represent a system problem. What did someone
  			// do to /dev/urandom?
  			panic(fmt.Errorf("error reading random number generator, retried for %v: %v", totalBackoff.String(), err))
  		}
  
  		break
  	}
  
  	s := base32.StdEncoding.EncodeToString(u)
  
  	return s[:l]
  }
docs: // generateID creates a new random string identifier with the given length