code: func (net *Network) ConnectToRandomNode(id enode.ID) (err error) {
  	net.lock.Lock()
  	defer net.lock.Unlock()
  
  	selected := net.getRandomUpNode(id)
  	if selected == nil {
  		return ErrNodeNotFound
  	}
  	return net.connectNotConnected(selected.ID(), id)
  }
docs: // ConnectToRandomNode connects the node with provided NodeID
  // to a random node that is up.