code: def test_value(self, input_param, input_data, expected_val):
      layer = DVF2DDF(**input_param)
      result = layer(**input_data)
      np.testing.assert_allclose(
          result.cpu().numpy(),
          expected_val.cpu().numpy(),
          rtol=1e-4,
          atol=1e-4,
      )
  
file_path: MONAI/tests/test_dvf2ddf.py
imports: from __future__ import annotations
  import unittest
  import numpy
  import torch
  from parameterized import parameterized
  from torch import nn
  from torch.optim import SGD
  from monai.networks.blocks.warp import DVF2DDF
  from monai.utils import set_determinism
label_desc: Use image node_id 3 for calling the TestDVF2DDF obj's underlying member method code with example usage: obj.test_value(input_param, input_data, expected_val) without return types