@classmethod
  @gen.coroutine
  def NotifyUpdateFollower(cls, client, foll_dict):
    """Adds a notification for the current user that follower metadata has changed. Since this
    only affects that user, invalidates the viewpoint metadata only for that user. No activity
    is created, since other followers of the viewpoint are not affected by this action.
    """
    viewpoint_id = foll_dict['viewpoint_id']

    # Do full viewpoint metadata invalidation by default.
    seq_num_pair = None
    invalidate = {'viewpoints': [{'viewpoint_id': viewpoint_id,
                                  'get_attributes': True}]}

    if foll_dict in 'viewed_seq':
      # In-line the viewed_seq field since it was updated.
      seq_num_pair = (None, foll_dict['viewed_seq'])
      if len(foll_dict) == 2:
        # Only the viewed_seq attribute was updated, so no need to send full invalidation (since it is in-line).
        invalidate = None

    yield NotificationManager.CreateForUser(client,
                                            NotificationManager._GetOperation().user_id,
                                            'update_follower',
                                            invalidate=invalidate,
                                            viewpoint_id=viewpoint_id,
                                            seq_num_pair=seq_num_pair)
dataset/ETHPy150Open viewfinderco/viewfinder/backend/op/notification_manager.py/NotificationManager.NotifyUpdateFollower/swapped operands of `in`