code: func (task *Task) SetPullStartedAt(timestamp time.Time) bool {
  	task.lock.Lock()
  	defer task.lock.Unlock()
  
  	// Only set this field if it is not set
  	if task.PullStartedAtUnsafe.IsZero() {
  		task.PullStartedAtUnsafe = timestamp
  		return true
  	}
  	return false
  }
docs: // SetPullStartedAt sets the task pullstartedat timestamp and returns whether
  // this field was updated or not