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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 reserved_quota(self, reserved_quota):
 """ Sets the reserved_quota of this ServicePackageMetadata. Sum of all open reservations for this account. :param reserved_quota: The reserved_quota of this ServicePackageMetadata. :type: int """

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

        self._reserved_quota = reserved_quota