code: def read_split_file(split_file):
      """
      Read a split file for ALT
  
      The format of the file is expected to be a list of lines such as
      URL.1234    <url>
      Here, we only care about the id
  
      return: a set of the ids
      """
      with open(split_file, encoding="utf-8") as fin:
          lines = fin.readlines()
      lines = [x.strip() for x in lines]
      lines = [x.split()[0] for x in lines if x]
      if any(not x.startswith("URL.") for x in lines):
          raise ValueError(
              "Unexpected line in %s: %s" % (split_file, x)
          )
      split = set(int(x.split(".", 1)[1]) for x in lines)
      return split
  
label_desc: Use image node_id 1 for calling a global function with example usage: read_split_file(split_file) and returns: split