docs: def slugify(value, separator="-"):
      """Slugify an Unicode string, to make it URL friendly."""
      if not isinstance(value, str):
          raise ValueError("value must be a Unicode string")
      value = _NOT_WORD_RE.sub(" ", value)
      value = unicodedata.normalize("NFKD", value)
      value = value.encode("ascii", "ignore")
      value = value.decode("ascii")
      value = value.strip().lower()
      value = re.sub(fr"[{separator}_\s]+", separator, value)
      return value