def _last_index(self, s):
        self.set_index(max(0, self._find_one_after_last_labeled_index() - 1))
def current_label(self) -> ProtocolLabel:
        if len(self.message.message_type) == 0:
            return None

        cur_label = self.message.message_type[self.current_label_index].get_copy()
        self.message.message_type[self.current_label_index] = cur_label
        cur_label.fuzz_values = [fv for fv in cur_label.fuzz_values if fv]  # Remove empty strings

        if len(cur_label.fuzz_values) == 0:
            cur_label.fuzz_values.append(self.message.plain_bits_str[cur_label.start:cur_label.end])
        return cur_label