code: def build(opt):
      dpath = os.path.join(opt["datapath"], "WikiQA")
      version = None
  
      if not build_data.built(dpath, version_string=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              # An older version exists, so remove these outdated files.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)
  
          dpext = os.path.join(dpath, "WikiQACorpus")
          create_fb_format(
              dpath, "train", os.path.join(dpext, "WikiQA-train.tsv")
          )
          create_fb_format(
              dpath, "valid", os.path.join(dpext, "WikiQA-dev.tsv")
          )
          create_fb_format(
              dpath, "test", os.path.join(dpext, "WikiQA-test.tsv")
          )
          create_fb_format(
              dpath,
              "train-filtered",
              os.path.join(dpext, "WikiQA-train.tsv"),
          )
          create_fb_format(
              dpath,
              "valid-filtered",
              os.path.join(dpext, "WikiQA-dev.tsv"),
          )
          create_fb_format(
              dpath,
              "test-filtered",
              os.path.join(dpext, "WikiQA-test.tsv"),
          )
  
          # Mark the data as built.
          build_data.mark_done(dpath, version_string=version)
  
imports: import parlai.core.build_data
  import os
  from parlai.core.build_data import DownloadableFile
  from parlai.utils.io import PathManager
label_desc: Use image node_id 2 for calling a global function with example usage: build(opt) without return types