code: def download_file(download_url, target_filepath, max_bytes=MAX_FILE_DEFAULT):
      
      response = requests.get(download_url, stream=True)
      size = int(response.headers['Content-Length'])
  
      if _exceeds_size(size, max_bytes, target_filepath) is True:
          return response
  
      logging.info('Downloading {} ({})'.format(
          target_filepath, format_size(size)))
  
      if os.path.exists(target_filepath):
          stat = os.stat(target_filepath)
          if stat.st_size == size:
              logging.info('Skipping, file exists and is the right '
                           'size: {}'.format(target_filepath))
              return response
          else:
              logging.info('Replacing, file exists and is the wrong '
                           'size: {}'.format(target_filepath))
              os.remove(target_filepath)
  
      with open(target_filepath, 'wb') as f:
          for chunk in response.iter_content(chunk_size=8192):
              if chunk:
                  f.write(chunk)
  
      logging.info('Download complete: {}'.format(target_filepath))
      return response
docs: Download a file.
  
      :param download_url: This field is the url from which data will be
          downloaded.
      :param target_filepath: This field is the path of the file where
          data will be downloaded.
      :param max_bytes: This field is the maximum file size to download. Its
          default value is 128m.