code: func (i *TeleInstance) GetSiteAPI(siteName string) auth.ClientI {
  	siteTunnel, err := i.Tunnel.GetSite(siteName)
  	if err != nil {
  		log.Warn(err)
  		return nil
  	}
  	siteAPI, err := siteTunnel.GetClient()
  	if err != nil {
  		log.Warn(err)
  		return nil
  	}
  	return siteAPI
  }
docs: // GetSiteAPI() is a helper which returns an API endpoint to a site with
  // a given name. i endpoint implements HTTP-over-SSH access to the
  // site's auth server.