@classmethod
  @gen.coroutine
  def _FormatAddFollowersText(cls, client, viewpoint, activity):
    sharer_name = yield AlertManager._GetNameFromUserId(client, activity.user_id)
    raise gen.Return('%s added you to a conversation%s' % (sharer_name, AlertManager._GetViewpointTitle(viewpoint)))
@Application.argument decorator should register a command with a specific argument
dataset/ETHPy150Open viewfinderco/viewfinder/backend/op/alert_manager.py/AlertManager._FormatAddFollowersText--crossover with--dataset/ETHPy150Open sdispater/cleo/tests/test_application.py/ApplicationTest.test_argument_decorator