Python Pick two random items from list not previously chosen together

I'm pretty new to Python, just going through a good course on Udemy but I have an issue with a little pet project of mine.

I'm trying to write code to help rank favourite games/films etc from a list. The code chooses two items at random from the list then asks the user to choose one. This choice is recorded in a dictionary. A next set of 2 are then given to the user until the number of battles matches the total possible.

All works ok, but I can't figure out how to ensure each new random choice of 2 has not been picked before. My idea was to create a tuple of the two items and append it (and its inverse) to a list. Then check if the random choice is in this list, it would try the random choice again.

I just can't get my head around the ordering of things at all.

The pertinent code is:

import math
my_games = ['A', 'B', 'C']

def random_two(game_list):
    import random
    two_games = []
    while len(two_games) < 2:
        rndm = random.choice(game_list)
        if rndm not in two_games:
            two_games.append(rndm)
        else:
            pass
    return two_games

battle_num = 1
initial_scores = [0]* len(my_games)
game_dict = dict(zip(my_games, initial_scores))
game_battles = []
def choose_games(game_list):
    global battle_num
    global initial_scores
    global game_dict
    global game_battles
    
    while tuple(random_two(game_list)) in game_battles:
        random_two(game_list)
    else: ?
      
#In here I don't know what to do. Initially "two_game" was just part of this func, but I dropped it outside to call it more easily.
        
        
    tupl_games1 = tuple(two_games)
    tupl_games2 = tuple(two_games[::-1])
    game_battles.append(tupl_games1)
    game_battles.append(tupl_games2)
    choice = int(input(f'Please choose game 1 - {two_games[0]}, or game 2 - {two_games[1]}'))
    if choice not in (1,2):
        print('You must choose 1 or 2')
        choice = int(input(f'Please choose game 1 - {two_games[0]}, or game 2 - {two_games[1]}'))
    else: 
        print(f'You chose {two_games[choice-1]}')
        game_dict[two_games[choice-1]] += 1
    #print(tupl_games1)
    #print(tupl_games2)
    #print(battle_num)   
    #print(game_battles)
    battle_num = battle_num +1