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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 _check_quota(self):
 """ If IP can't make requests, raise BitQuotaExceeded. Called before generating numbers. """

        self._request_remaining_quota_if_unset()
        if self.quota_estimate < self.quota_limit:
            raise BitQuotaExceeded(self.quota_estimate)