code: func (sn *SimNode) ServiceMap() map[string]node.Service {
  	sn.lock.RLock()
  	defer sn.lock.RUnlock()
  	services := make(map[string]node.Service, len(sn.running))
  	for name, service := range sn.running {
  		services[name] = service
  	}
  	return services
  }
docs: // ServiceMap returns a map by names of the underlying services