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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 __set_method(self, value):
        '''
        Sets the amount of the payment.
        '''
        if value not in [PAYMENT_METHOD_OTHER, PAYMENT_METHOD_CARD,
                         PAYMENT_METHOD_CHEQUE, PAYMENT_METHOD_CASH, ]:
            raise ValueError('Invalid amount value')

        self.__method = value