def METHOD_NAME(self):
    evaluator = Evaluator(function=self.f)
    candidates = pd.DataFrame(np.random.rand(10, 2), columns=["x1", "x2"])
    futures = evaluator.submit_data(candidates)
    assert len(futures) == 10
    # try with a bad function
    evaluator = Evaluator(function=self.g)
    candidates = pd.DataFrame(np.random.rand(10, 2), columns=["x1", "x2"])
    futures = evaluator.submit_data(candidates)
    assert len(futures) == 10