code: def __maybe_download_file(destination: str, source: str):
      """
      Downloads source to destination if it doesn't exist.
      If exists, skips download
      Args:
          destination: local filepath
          source: url of resource
      Returns:
      """
      source = URLS[source]
      if not os.path.exists(destination):
          logging.info(
              "{0} does not exist. Downloading ...".format(destination)
          )
          urllib.request.urlretrieve(
              source, filename=destination + ".tmp"
          )
          os.rename(destination + ".tmp", destination)
          logging.info("Downloaded {0}.".format(destination))
      else:
          logging.info(
              "Destination {0} exists. Skipping.".format(destination)
          )
      return destination
  
file_path: NeMo/scripts/dataset_processing/get_demand_data.py
imports: import argparse
  import glob
  import json
  import logging
  import os
  import shutil
  import subprocess
  import urllib.request
label_desc: Use image node_id 1 for calling a global function with example usage: __maybe_download_file(destination, source) and returns: destination