code: func (s *UDPSession) SetDeadline(t time.Time) error {
  	s.mu.Lock()
  	defer s.mu.Unlock()
  	s.rd = t
  	s.wd = t
  	s.notifyReadEvent()
  	s.notifyWriteEvent()
  	return nil
  }
docs: // SetDeadline sets the deadline associated with the listener. A zero time value disables the deadline.