@capture_logging(None)
    def test_scenario_throws_exception_when_already_started(self, _logger):
        c = Clock()
        cluster = self.make_cluster(self.get_fake_flocker_client_instance())
        sample_size = 5
        s = write_request_load_scenario(c, cluster, sample_size=sample_size)
        # Start and stop
        s.start()
        c.pump(repeat(1, sample_size))
        self.assertRaises(RequestScenarioAlreadyStarted, s.start)
start method in the ``RequestLoadScenario`` throws a
dataset/ETHPy150Open ClusterHQ/flocker/benchmark/scenarios/test/test_write_request_load.py/write_request_load_scenarioTest.test_scenario_throws_exception_when_already_started