code: func (si *shareImporter) isAssembled() (bool, error) {
  	u, err := url.Parse(si.shareURL)
  	if err != nil {
  		return false, err
  	}
  	isAs, _ := strconv.ParseBool(u.Query().Get("assemble"))
  	return isAs, nil
  }
docs: // isAssembled reports whether si.shareURL is of a shared assembled file.