code: def download(self):
          
          from .tasks import download_file
          if not settings.LOCALSHOP_ISOLATED:
              download_file.delay(pk=self.pk)
          else:
              download_file(pk=self.pk)
docs: Start a celery task to download the release file from pypi.
  
          If `settings.LOCALSHOP_ISOLATED` is True then download the file
          in-process.