docs: def download_file(local_filename, url, clobber=False):
      """Download the given file. Clobber overwrites file if exists."""
      dir_name = os.path.dirname(local_filename)
      mkdirs(dir_name)
  
      if clobber or not os.path.exists(local_filename):
          i = requests.get(url)
  
          # if not exists
          if i.status_code == 404:
              print('Failed to download file:', local_filename, url)
              return False
  
          # write out in 1MB chunks
          chunk_size_in_bytes = 1024*1024  # 1MB
          with open(local_filename, 'wb') as local_file:
              for chunk in i.iter_content(chunk_size=chunk_size_in_bytes):
                  local_file.write(chunk)
  
      return True