code: def _download_file(uri, bulk_api):
      
      resp = requests.get(uri, headers=bulk_api.headers(), stream=True)
      with tempfile.TemporaryFile("w+b") as f:
          for chunk in resp.iter_content(chunk_size=None):
              f.write(chunk)
          f.seek(0)
          yield f
docs: Download the bulk API result file for a single batch