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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 amount(self, amount):
 """ Sets the amount of this Money. The amount of money, in the smallest denomination of the currency indicated by `currency`. For example, when `currency` is `USD`, `amount` is in cents. :param amount: The amount of this Money. :type: int """


        if amount is None:
            raise ValueError("Invalid value for `amount`, must not be `None`")
        if amount < 0:
            raise ValueError("Invalid value for `amount`, must be a value greater than or equal to `0`")

        self._amount = amount