class_docstr: atis2 data class for nlu joint task.
code: def after_download(self) -> bool:
      try:
          shutil.move(
              os.path.join(self.download_dir, "JointSLU/data"),
              os.path.join(self.download_dir, "origin_data"),
          )
          shutil.rmtree(os.path.join(self.download_dir, "JointSLU"))
          self.to_standard_format(
              os.path.join(self.download_dir, self.train_download),
              os.path.join(self.data_dir, self.train_file),
          )
          self.to_standard_format(
              os.path.join(self.download_dir, self.dev_download),
              os.path.join(self.data_dir, self.dev_file),
          )
          self.to_standard_format(
              os.path.join(self.download_dir, self.test_download),
              os.path.join(self.data_dir, self.test_file),
          )
      except Exception as e:
          logging.warning(traceback.format_exc())
          return False
      return True
  
file_path: delta/delta/data/datasets/atis2.py
imports: import os
  from absl import logging
  import shutil
  import traceback
  from delta.data.datasets.base_dataset import BaseDataSet
  from delta.utils.register import registers
label_desc: Use image node_id 4 for calling the ATIS2 obj's underlying member method code with example usage: obj.after_download() and returns: True, False