@classmethod
  @gen.coroutine
  def NotifyReviveFollowers(cls, client, viewpoint_id, revive_follower_ids, timestamp):
    """Adds a notification for each of the followers that have been revived. The notification
    invalidates the entire viewpoint in order to force the client to load it in its entirety.
    """
    if len(revive_follower_ids) > 0:
      invalidate = {'viewpoints': [NotificationManager._CreateViewpointInvalidation(viewpoint_id)]}
      yield [NotificationManager.CreateForUser(client,
                                               follower_id,
                                               'revive followers',
                                               invalidate=invalidate,
                                               viewpoint_id=viewpoint_id)
             for follower_id in revive_follower_ids]
dataset/ETHPy150Open viewfinderco/viewfinder/backend/op/notification_manager.py/NotificationManager.NotifyReviveFollowers/original