code: func (state *DockerTaskEngineState) ContainerMapByArn(arn string) (map[string]*apicontainer.DockerContainer, bool) {
  	state.lock.RLock()
  	defer state.lock.RUnlock()
  
  	ret, ok := state.taskToID[arn]
  
  	// Copy the map to avoid data race
  	if ok {
  		mc := make(map[string]*apicontainer.DockerContainer)
  		for k, v := range ret {
  			mc[k] = v
  		}
  		return mc, ok
  	}
  
  	return ret, ok
  }
docs: // ContainerMapByArn returns a map of containers belonging to a particular task ARN