'Ensure query plan for a downed cluster will execute without errors'

def test_no_live_nodes(self):

    hosts = [0, 1, 2, 3]
    policy = RoundRobinPolicy()
    policy.populate(None, hosts)
    for i in range(4):
        policy.on_down(i)
    qplan = list(policy.make_query_plan())
    self.assertEqual(qplan, [])
