def _credit_card_type(self, card_type=None):
        """ Returns a random credit card type instance. """
        if card_type is None:
            card_type = self.random_element(self.credit_card_types.keys())
        elif isinstance(card_type, CreditCard):
            return card_type
        return self.credit_card_types[card_type]
def _credit_card_type ( self , card_type = None ) : if card_type is None : card_type = self . random_element ( self . credit_card_types . keys ( ) ) elif isinstance ( card_type , CreditCard ) : return card_type return self . credit_card_types [ card_type ]
Returns a random credit card type instance.