def _get_different_rank_list(self, all_cards):
        '''
        Get cards with different ranks, that is to say, remove duplicate-ranking cards, for picking straight cards' use
        Args:
            (list): two hand cards + five public cards
        Returns:
            (list): a list of cards with duplicate-ranking cards removed
        '''
        different_rank_list = []
        different_rank_list.append(all_cards[0])
        for card in all_cards:
            if(card[1] != different_rank_list[-1][1]):
                different_rank_list.append(card)
        return different_rank_list

        Get cards with different ranks, that is to say, remove duplicate-ranking cards, for picking straight cards' use
        Args:
            (list): two hand cards + five public cards
        Returns:
            (list): a list of cards with duplicate-ranking cards removed
        
rlcard/games/limitholdem/utils.py