def METHOD_NAME(self):
    lst = [1]
    def func():
        gevent.spawn_later(0.01, lst.pop)
        gevent.sleep(0.02)
    gevent.spawn(func)
    # Func has not run yet
    self.assertEqual(lst, [1])
    # Run callbacks but don't yield.
    gevent.sleep()
    # Let timers fire. Func should be done.
    gevent.sleep(0.1)
    self.assertEqual(lst, [])