code: func (s *creator) createGeneratePIN(ctx context.Context) (string, error) {
  	length, err := termio.AskForInt(ctx, fmtfn(4, "a", "How long?"), 4)
  	if err != nil {
  		return "", err
  	}
  	return pwgen.GeneratePasswordCharset(length, "0123456789"), nil
  }
docs: // createGeneratePIN will walk through the PIN generation steps