code: func (handler *TaskHandler) batchContainerEventUnsafe(event api.ContainerStateChange) {
  	seelog.Infof("TaskHandler: batching container event: %s", event.String())
  	handler.tasksToContainerStates[event.TaskArn] = append(handler.tasksToContainerStates[event.TaskArn], event)
  }
docs: // batchContainerEventUnsafe collects container state change events for a given task arn