code: func NewWithLockerOptions(client *etcd3.Client, opts LockerOptions) (*Etcd3Locker, error) {
  	locksMap := map[string]*etcd3Lock{}
  	return &Etcd3Locker{Client: client, prefix: opts.Prefix(), sessionTtl: opts.Ttl(), locks: locksMap, mutex: sync.Mutex{}}, nil
  }
docs: // This method may be used if we want control over both prefix/session TTLs. This is used for testing in particular.