docs: def _translate_symbols(string):
      """Given a description of a Greek letter or other special character,
      return the appropriate unicode letter."""
      res = []
      string = str(string)
      for s in re.split(r'(\W+)', string, flags=re.UNICODE):
          tex_str = _GREEK_DICTIONARY.get(s)
          if tex_str:
              res.append(tex_str)
          elif s.lower() in _GREEK_DICTIONARY:
              res.append(_GREEK_DICTIONARY[s])
          else:
              res.append(s)
      return "".join(res)