code: def _download_and_preprocess_data(data_dir):
      # Conditionally download data
      LDC93S1_BASE = "LDC93S1"
      LDC93S1_BASE_URL = "https://catalog.ldc.upenn.edu/desc/addenda/"
      local_file = maybe_download(
          LDC93S1_BASE + ".wav",
          data_dir,
          LDC93S1_BASE_URL + LDC93S1_BASE + ".wav",
      )
      trans_file = maybe_download(
          LDC93S1_BASE + ".txt",
          data_dir,
          LDC93S1_BASE_URL + LDC93S1_BASE + ".txt",
      )
      with open(trans_file, "r") as fin:
          transcript = " ".join(
              fin.read().strip().lower().split(" ")[2:]
          ).replace(".", "")
  
      df = pandas.DataFrame(
          data=[
              (
                  os.path.abspath(local_file),
                  os.path.getsize(local_file),
                  transcript,
              )
          ],
          columns=["wav_filename", "wav_filesize", "transcript"],
      )
      df.to_csv(os.path.join(data_dir, "ldc93s1.csv"), index=False)
  
imports: import os
  import sys
  import pandas
  from deepspeech_training.util.downloader import maybe_download
label_desc: Use image node_id 1 for calling a global function with example usage: _download_and_preprocess_data(data_dir) without return types