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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 _add_export(self, ed_id, inst):
 # type: (str, Tuple[Any, EndpointDescription]) -> None """ Keeps track of an exported service :param ed_id: ID of the endpoint description :param inst: A tuple: (service instance, endpoint description) """

        with self._exported_instances_lock:
            self._exported_services[ed_id] = inst