code: def build(opt):
      dpath = os.path.join(opt["datapath"], "image_chat")
      image_path = os.path.join(opt["datapath"], "yfcc_images")
      version = "1.0"
      if not build_data.built(dpath, version):
          print("[building data: " + dpath + "]")
          if build_data.built(dpath):
              # An older version exists, so remove these outdated files.
              build_data.remove_dir(dpath)
          build_data.make_dir(dpath)
  
          # Download the data.
          for downloadable_file in RESOURCES:
              downloadable_file.download_file(dpath)
  
          build_data.mark_done(dpath, version)
  
      if (
          not build_data.built(image_path, version)
          and not opt.get("yfcc_path")
          and opt.get("load_images")
      ):
          download_images(opt, task="image_chat")
  
imports: from parlai.core.build_data import DownloadableFile
  import parlai.core.build_data
  import os
  from parlai.tasks.personality_captions.download_images import download_images
label_desc: Use image node_id 1 for calling a global function with example usage: build(opt) without return types