def _runloop(self):
        while not self.server._stop:
            self.server.serve()
        while not self._stopped:
            time.sleep(0.1)
Returns unordered tiers. These must be in a random order.
dataset/ETHPy150Open facebook/sparts/sparts/tasks/thrift/nbserver.py/NBServerTask._runloop--crossover with--dataset/ETHPy150Open mozilla/app-validator/tests/test_submain.py/MockTestcases._get_tiers