def step_back(self, players):
        ''' Reverse the last action

        Args:
            players (list): list of DoudizhuPlayer objects
        Returns:
            The last player id and the cards played
        '''
        player_id, cards = self.trace.pop()
        self.current_player = player_id
        if (cards != 'pass'):
            for card in cards:
                # self.played_cards.remove(card)
                self.played_cards[player_id][CARD_RANK_STR_INDEX[card]] -= 1
            self.public['played_cards'] = self.cards_ndarray_to_str(self.played_cards)
        greater_player_id = self.find_last_greater_player_id_in_trace()
        if (greater_player_id is not None):
            self.greater_player = players[greater_player_id]
        else:
            self.greater_player = None
        return player_id, cards
 Reverse the last action

        Args:
            players (list): list of DoudizhuPlayer objects
        Returns:
            The last player id and the cards played
        
rlcard/games/doudizhu/round.py