code: func (bto *BootstrapTokenOptions) AddTTLFlagWithName(fs *pflag.FlagSet, flagName string) {
  	fs.DurationVar(
  		&bto.TTL.Duration, flagName, bto.TTL.Duration,
  		"The duration before the token is automatically deleted (e.g. 1s, 2m, 3h). If set to '0', the token will never expire",
  	)
  }
docs: // AddTTLFlagWithName adds the --token-ttl flag with a custom flag name given flagset