docs: public static Tree buildTree(TreebankNode node) throws Exception {
          if (node.getLeaf())
              return toTree(node);
          else {
              List<TreebankNode> preChildren = children(node);
              List<Tree> children = new ArrayList<>();
              Tree t = toTree(node);
              for (int i = 0; i < preChildren.size(); i++) {
                  children.add(buildTree(preChildren.get(i)));
              }
  
              t.connect(children);
              return t;
  
          }
  
  
  
      }