code: def test_gradcheck(self, device):
      boxes = torch.tensor(
          [[[1.0, 1.0], [3.0, 1.0], [3.0, 2.0], [1.0, 2.0]]],
          device=device,
      )
      boxes = tensor_to_gradcheck_var(boxes)
      gradcheck(infer_bbox_shape, (boxes,))
  
imports: import torch
  import kornia
  from kornia.geometry.bbox import infer_bbox_shape, infer_bbox_shape3d, nms, transform_bbox, validate_bbox, validate_bbox3d
  from kornia.testing import assert_close, gradcheck, tensor_to_gradcheck_var
label_desc: Use image node_id 4 for calling the TestBbox2D obj's underlying member method code with example usage: obj.test_gradcheck(device) without return types