code: def _escaped_token_to_subtoken_strings(self, escaped_token):
      
      # NOTE: This algorithm is greedy; it won't necessarily produce the "best"
      # list of subtokens.
      ret = []
      start = 0
      token_len = len(escaped_token)
      while start < token_len:
        for end in range(
            min(token_len, start + self._max_subtoken_len), start, -1):
          subtoken = escaped_token[start:end]
          if subtoken in self._subtoken_string_to_id:
            ret.append(subtoken)
            start = end
            break
  
        else:  # Did not break
          # If there is no possible encoding of the escaped token then one of the
          # characters in the token is not in the alphabet. This should be
          # impossible and would be indicative of a bug.
          assert False, "Token substring not found in subtoken vocabulary."
  
      return ret
docs: Converts an escaped token string to a list of subtoken strings.
  
      Args:
        escaped_token: An escaped token as a unicode string.
      Returns:
        A list of subtokens as unicode strings.