What are the possible alternatives to making all variables in a function global in Python?

Question

Okay, so I know you shouldn't /really/ make variables global - they're meant to be local. However I am programming a blackjack game and I need to reset the cards every time the user wants to play again - so I have made a function called 'reset' and it calls that if the it is going to repeat. My main question is, should I do this or is there a better method of solving my problem, or is there a better way of doing this than just typing out global _____ every time? Here's my code if anyone wants to see;

import random
playagain = True
def reset():
    global cards
    global gameCards
    global playerCards
    global cpuCards
    global pgameCards
    global cpugameCards
    global start
    cards = ["A♠", "2♠", "3♠", "4♠", "5♠", "6♠", "7♠", "8♠", "9♠", "10♠", "J♠", "Q♠", "K♠",
             "A♥", "2♥", "3♥", "4♥", "5♥", "6♥", "7♥", "8♥", "9♥", "10♥", "J♥", "Q♥", "K♥",
             "A♣", "2♣", "3♣", "4♣", "5♣", "6♣", "7♣", "8♣", "9♣", "10♣", "J♣", "Q♣", "K♣",
             "A♦", "2♦", "3♦", "4♦", "5♦", "6♦", "7♦", "8♦", "9♦", "10♦", "J♦", "Q♦", "K♦"]
    gameCards = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10]
    playerCards = []
    cpuCards = []
    pgameCards = []
    cpugameCards = []
    start = 0

[...]

while playagain == True:
    reset()
    winner = game()
    print("Your cards: ", playerCards)
    print("CPU's cards: ", cpuCards)
    print(winner)
    askUser = input("Play again? Y/N ")
    if askUser.upper() == "Y":
        playagain = True
    else:
        playagain = False

Answer 1

Just to give a notch in the right direction:

import random

playagain = True

class Game:
    def __init__(self):
        # init all members
        pass

    def Reset(self):
        self.cards = ["A?", "2?", "3?", "4?", "5?", "6?", "7?", "8?", "9?", "10?", "J?", "Q?", "K?",
                 "A?", "2?", "3?", "4?", "5?", "6?", "7?", "8?", "9?", "10?", "J?", "Q?", "K?",
                 "A?", "2?", "3?", "4?", "5?", "6?", "7?", "8?", "9?", "10?", "J?", "Q?", "K?",
                 "A?", "2?", "3?", "4?", "5?", "6?", "7?", "8?", "9?", "10?", "J?", "Q?", "K?"]
        self.gameCards = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                     1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10]
        self.playerCards = []
        self.cpuCards = []
        self.pgameCards = []
        self.cpugameCards = []
        self.start = 0

Here you have an Object that holds all methods the object can do. You have to read a bit about object oriented programming and learn about the way it is implemented in python.

Answer 2

Using Global variables is a feature of python but if you want to code elegantly I believe global variables shouldn't be used at all.

I like to pass variables from function to function instead. My solution may not look very elegant but it actually is in my opinion.

Note: I have also included the 3 print statements into the game() function to make it simpler since they are called no matter what the output of game is.

Here is my solution:

import random
playagain = True
def reset():
    cards = ["A♠", "2♠", "3♠", "4♠", "5♠", "6♠", "7♠", "8♠", "9♠", "10♠", "J♠", "Q♠", "K♠",
             "A♥", "2♥", "3♥", "4♥", "5♥", "6♥", "7♥", "8♥", "9♥", "10♥", "J♥", "Q♥", "K♥",
             "A♣", "2♣", "3♣", "4♣", "5♣", "6♣", "7♣", "8♣", "9♣", "10♣", "J♣", "Q♣", "K♣",
             "A♦", "2♦", "3♦", "4♦", "5♦", "6♦", "7♦", "8♦", "9♦", "10♦", "J♦", "Q♦", "K♦"]
    gameCards = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10,
                 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 10, 10, 10]
    playerCards = []
    cpuCards = []
    pgameCards = []
    cpugameCards = []
    start = 0
    return cards, gameCards, playerCards, cpuCards, pgameCards, cpugameCards, start



def game(cards, gameCards, playerCards, cpuCards, pgameCards, cpugameCards, start):

    # [Main Code]

    winner = 'abcd' # put whatever you return from your original game() function as the value of winner 
    print("Your cards: ", playerCards)
    print("CPU's cards: ", cpuCards)
    print(winner)

while playagain == True:
    cards, gameCards, playerCards, cpuCards, pgameCards, cpugameCards, start = reset()
    game(cards, gameCards, playerCards, cpuCards, pgameCards, cpugameCards, start)
    askUser = input("Play again? Y/N ")
    if askUser.upper() == "Y":
        playagain = True
    else:
        playagain = False

Answer 3

Extending on What's answer, instead of resting all the cards in the game you could delete the current Game object and create new object. And then set all your initial states within a init function. Below is a example

import random

class Game:
    cards = []
    gameCards = []
    playerCards = []
    pgameCards = []
    cpugameCards = []
    start = 0
    '''+all your class attributes'''

    def __init__(self):
        '''insert your initial states here'''
        pass

Then to start a new game you would do something like the following:

'''To start a new game'''
game = Game()

Then to finish the current game you could do something like the following:

'''To end the current game'''
del game

If your resetting a game aren't you technically creating a new game? That's why I recommend creating and deleting game objects

Reason why you do not want to deal with global variables can be found here

All the best with your game!