code: def build(opt):
      version = MSC_DATASETS_VERSION
      # create particular instance of dataset depending on flags..
      dpath = get_msc_dir_path(opt)
      if not build_data.built(dpath, version):
          logger.warning("[build 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              # An older version exists, so remove these outdated files.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)
          for downloadable_file in RESOURCES:
              downloadable_file.download_file(dpath)
          # Mark the data as built.
          build_data.mark_done(dpath, version)
  
      return dpath
  
imports: import parlai.core.build_data
  import os
  from parlai.utils.logging import logger
  from parlai.core.build_data import DownloadableFile
label_desc: Use image node_id 2 for calling a global function with example usage: build(opt) and returns: dpath