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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def empty(self, return_cards=False):
 """ Empties the stack, removing all cards from it, and returns them. :arg bool return_cards: Whether or not to return the cards. :returns: If ``return_cards=True``, a list containing the cards removed from the Stack. """

        cards = list(self.cards)
        self.cards = []

        if return_cards:
            return cards