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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 quota(self, quota):
 """ Sets the quota of this ServicePackageQuota. Available quota for the service package. :param quota: The quota of this ServicePackageQuota. :type: int """

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

        self._quota = quota