def load(self):
        if os.path.exists(self.path):
            with open(self.path, 'r') as f:
                self.body_labels = collections.OrderedDict(json.load(f))
def test_impl():
            A = np.array([1., 2., 3.])
            A[0] = 4.0
            df = pd.DataFrame({'A': A})
            return df.A.std()