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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 card_nonce(self, card_nonce):
 """ Sets the card_nonce of this ChargeRequest. A nonce generated from the `SqPaymentForm` that represents the card to charge. The application that provides a nonce to this endpoint must be the _same application_ that generated the nonce with the `SqPaymentForm`. Otherwise, the nonce is invalid. Do not provide a value for this field if you provide a value for `customer_card_id`. :param card_nonce: The card_nonce of this ChargeRequest. :type: str """


        if card_nonce is None:
            raise ValueError("Invalid value for `card_nonce`, must not be `None`")
        if len(card_nonce) > 192:
            raise ValueError("Invalid value for `card_nonce`, length must be less than `192`")

        self._card_nonce = card_nonce