def _get_coordinator_for_group(self, consumer_group):
        """Returns the coordinator (broker) for a consumer group

        Returns the broker for a given consumer group or
        Raises ConsumerCoordinatorNotAvailableError
        """
        if self.consumer_group_to_brokers.get(consumer_group) is None:
            yield self.load_consumer_metadata_for_group(consumer_group)

        returnValue(self.consumer_group_to_brokers.get(consumer_group))