docs: def slugify_unicode(s):
      """
      Replacement for Django's slugify which allows unicode chars in
      slugs, for URLs in Chinese, Russian, etc.
      Adopted from https://github.com/mozilla/unicode-slugify/
      """
      chars = []
      for char in str(smart_text(s)):
          cat = unicodedata.category(char)[0]
          if cat in "LN" or char in "-_~":
              chars.append(char)
          elif cat == "Z":
              chars.append(" ")
      return re.sub("[-\s]+", "-", "".join(chars).strip()).lower()