code: func (p *FakePeer) RequestNodeData(hashes []common.Hash) error {
  	var data [][]byte
  	for _, hash := range hashes {
  		if entry, err := p.db.Get(hash.Bytes()); err == nil {
  			data = append(data, entry)
  		}
  	}
  	p.dl.DeliverNodeData(p.id, data)
  	return nil
  }
docs: // RequestNodeData implements downloader.Peer, returning a batch of state trie
  // nodes corresponding to the specified trie hashes.