checkArgument(
          edge.length() == 2, "Expecting each edge to consist of 2 characters but got %s", edge);
      char node1 = edge.charAt(0);
      char node2 = edge.charAt(1);
      graphMapBuilder.put(node1, node2);
      if (!directed) {
        graphMapBuilder.put(node2, node1);
      }
    }
    ImmutableMultimap<Character, Character> graphMap = graphMapBuilder.build();

  /**
   * Remove {@code node} from the set of successors. Returns the value previously associated with
   * the edge connecting the two nodes.
   */
  @CanIgnoreReturnValue
  @Nullable V removeSuccessor(N node);

  /**
   * Add {@code node} as a predecessor to the origin node. In the case of an undirected graph, it
   * also becomes a successor. Associates {@code value} with the edge connecting the two nodes.
   */

   *         <li>{@code predecessors(node)}: Connecting edge insertion order
   *         <li>{@code successors(node)}: Connecting edge insertion order
   *         <li>{@code incidentEdges(node)}: Stable order
   *         <li>{@code inEdges(node)}: Edge insertion order
   *         <li>{@code outEdges(node)}: Edge insertion order
   *         <li>{@code adjacentEdges(edge)}: Stable order

   *         <li>{@code predecessors(node)}: Connecting edge insertion order
   *         <li>{@code successors(node)}: Connecting edge insertion order
   *         <li>{@code incidentEdges(node)}: Stable order
   *         <li>{@code inEdges(node)}: Edge insertion order
   *         <li>{@code outEdges(node)}: Edge insertion order
   *         <li>{@code adjacentEdges(edge)}: Stable order

     *      org.apache.maven.artifact.resolver.ResolutionNode)
     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        return node1.getDepth() >= node2.getDepth() ? node1 : node2;
    }

     */

    @Override
    public ResolutionNode resolveConflict(ResolutionNode node1, ResolutionNode node2) {
        try {
            ArtifactVersion version1 = node1.getArtifact().getSelectedVersion();
            ArtifactVersion version2 = node2.getArtifact().getSelectedVersion();

            return version1.compareTo(version2) > 0 ? node1 : node2;
        } catch (OverConstrainedVersionException exception) {

    protected abstract void doWrite(XmlNode node, Writer writer) throws IOException;

    /**
     * Implementation method for merging two XML nodes.
     *
     * @param dominant the dominant (higher priority) XML node
     * @param recessive the recessive (lower priority) XML node
     * @param childMergeOverride optional override for the child merge mode
     * @return the merged XML node, or null if both inputs are null
     */

    /**
     * Use an XPath string to select a single node.
     *
     * @param contextNode The node to start searching from.
     * @param expression A valid XPath string.
     * @return The first node found that matches the XPath, or null.
     *
     * @throws XPathExpressionException if an XPath expression error occurs.
     */

        nodes.add(node);
    }

    /**
     * find a node by the GAV (metadata)
     *
     * @param md
     */
    public MetadataGraphNode findNode(MavenArtifactMetadata md) {
        for (MetadataGraphNode mgn : nodes) {
            if (mgn.metadata.equals(md)) {
                return mgn;
            }
        }

        MetadataGraphNode node = new MetadataGraphNode(md);
        addNode(node);

    name: str


class Labels(BaseModel):
    nodes: list[LabelNode]


class ReviewNode(BaseModel):
    author: Author | None = None
    state: str


class Reviews(BaseModel):
    nodes: list[ReviewNode]


class PullRequestNode(BaseModel):
    number: int
    labels: Labels
    author: Author | None = None
    title: str
    createdAt: datetime
    lastEditedAt: datetime | None = None