code: func (task *Task) RecordExecutionStoppedAt(container *apicontainer.Container) {
  	if !container.Essential {
  		return
  	}
  	if container.GetKnownStatus() != apicontainerstatus.ContainerStopped {
  		return
  	}
  	// If the essential container is stopped, set the ExecutionStoppedAt timestamp
  	now := time.Now()
  	ok := task.SetExecutionStoppedAt(now)
  	if !ok {
  		// ExecutionStoppedAt was already recorded. Nothing to left to do here
  		return
  	}
  	seelog.Infof("Task [%s]: recording execution stopped time. Essential container [%s] stopped at: %s",
  		task.Arn, container.Name, now.String())
  }
docs: // RecordExecutionStoppedAt checks if this is an essential container stopped
  // and set the task executionStoppedAt timestamps