code: func StatusFlag(status *pb.Status) flag.Getter {
  	if status == nil {
  		panic("status is nil")
  	}
  	return &statusFlag{status}
  }
docs: // StatusFlag returns a flag.Getter which reads a flag value into status.
  // Valid flag values: scheduled, started, ended, success, failure, infra_faiure,
  // canceled.
  // Panics if status is nil.