code: def convert_alt(input_files, split_files, output_files):
      """
      Convert the ALT treebank into train/dev/test splits
  
      input_files: paths to read trees
      split_files: recommended splits from the ALT page
      output_files: where to write train/dev/test
      """
      all_lines = read_alt_lines(input_files)
  
      splits = [
          read_split_file(split_file) for split_file in split_files
      ]
      trees = split_trees(all_lines, splits)
  
      for chunk, output_file in zip(trees, output_files):
          print("Writing %d trees to %s" % (len(chunk), output_file))
          with open(output_file, "w", encoding="utf-8") as fout:
              for tree in chunk:
                  # the extra ROOT is because the ALT doesn't have this at the top of its trees
                  fout.write("(ROOT {})\n".format(tree))
  
label_desc: Use image node_id 4 for calling a global function with example usage: convert_alt(input_files, split_files, output_files) without return types