How to properly define a return string within a for loop for a Class using OOP in Python

I want to create a card deck using OOP in Python. I have two classes, Card and Deck, and I want to print all cards in a deck. However, I am not sure how to handle this problem because I can print the values (or rather return a string) in the Card class, in the Deck class and using __str__() or another method (showCard()). I am convinced the proper way to print all cards in the deck us by accessing a method in the Card class. I think the best way to do this is to utilize the __str__() method in Card, but all examples I found define a new print method (such as showCard()).

The issue is that the proper way of printing in OOP is by returning a string. However, this fails when I use the for loop to loop over all suits and values.

Code:

import random

class Deck:

    SUITS = ['Clubs', 'Spades', 'Hearts', 'Diamonds']
    VALUES = ['A', '2', '3', '4', '5', '6', '7', '8', '9', '10', 'J', 'Q', 'K']

    def __init__(self):
        self.deck = []
        self.createADeck()
        
    def createADeck(self):
        for value in self.VALUES:
            for suit in self.SUITS:
                self.deck.append(Card(suit, value))
                
    def shuffle(self):
        random.shuffle(self.deck)

    def __str__(self):
        for card in self.deck:
            card.__str__() # I DON'T KNOW WHAT TO PUT HERE
    
    
    
class Card:
    def __init__(self, suit, value):
        self.suit = suit
        self.value = value
        
    def showCard(self):
        print(f"The {self.value} of {self.suit}")
    
    def __str__(self):
        return f"The {self.value} of {self.suit}"

>Solution :

You need to assemble the entire string in the loop, and return it only after the loop is finished. This can be done in multiple ways, e.g.

    def __str__(self):
        s = ""
        for card in self.deck:
            s += str(card)
            s += "\n"
        return s

or

    def __str__(self):
        return "\n".join(str(card) for card in self.deck)