code: func (t *Transport) Active(id uint64) bool {
  	t.mu.Lock()
  	defer t.mu.Unlock()
  	p, ok := t.peers[id]
  	if !ok {
  		return false
  	}
  	p.mu.Lock()
  	active := p.active
  	p.mu.Unlock()
  	return active
  }
docs: // Active returns true if node was recently active and false otherwise.