func (t *T) Failed() bool {
	t.mu.Lock()
	defer t.mu.Unlock()
	return t.failed
}
func (t *T) Failed() bool {
	t.mu.Lock()
	defer t.mu.Unlock()
	return t.failed
}
func ( t * T ) Failed ( ) bool { t . mu . Lock ( ) defer t . mu . Unlock ( ) return t . failed }
// Failed checks if the task has failed
Failed checks if the task has failed