code: func newAttachENIHandler(ctx context.Context,
  	cluster string,
  	containerInstanceArn string,
  	acsClient wsclient.ClientServer,
  	taskEngineState dockerstate.TaskEngineState,
  	saver statemanager.Saver) attachENIHandler {
  
  	// Create a cancelable context from the parent context
  	derivedContext, cancel := context.WithCancel(ctx)
  	return attachENIHandler{
  		messageBuffer:     make(chan *ecsacs.AttachTaskNetworkInterfacesMessage),
  		ctx:               derivedContext,
  		cancel:            cancel,
  		cluster:           aws.String(cluster),
  		containerInstance: aws.String(containerInstanceArn),
  		acsClient:         acsClient,
  		state:             taskEngineState,
  		saver:             saver,
  	}
  }
docs: // newAttachENIHandler returns an instance of the attachENIHandler struct