docs: def download_if_not_exists(url: str, filename: str,
                             skip_cert_verify: bool = True,
                             mkdir: bool = True) -> None:
      """
      Downloads a URL to a file, unless the file already exists.
      """
      if os.path.isfile(filename):
          log.info("No need to download, already have: {}", filename)
          return
      if mkdir:
          directory, basename = os.path.split(os.path.abspath(filename))
          mkdir_p(directory)
      download(url=url,
               filename=filename,
               skip_cert_verify=skip_cert_verify)