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 sls(n, d):
            gg = te.reduce_axis((0, lengths[n]))
            indices_idx = length_offsets[n] + gg
            data_idx = indices[indices_idx]
            data_val = data[data_idx, d]
            return te.sum(data_val, axis=gg)