code: func (e *Etcd) Services(state request.Request, exact bool, opt plugin.Options) (services []msg.Service, err error) {
  	services, err = e.Records(state, exact)
  	if err != nil {
  		return
  	}
  
  	services = msg.Group(services)
  	return
  }
docs: // Services implements the ServiceBackend interface.