code: def test_gradcheck(self, device):
      scale_factor = torch.ones(
          1, device=device, dtype=torch.float64, requires_grad=True
      )
      camera_matrix = torch.ones(
          1, 3, 3, device=device, dtype=torch.float64
      )
      assert gradcheck(
          epi.scale_intrinsics,
          (camera_matrix, scale_factor),
          raise_exception=True,
          fast_mode=True,
      )
  
imports: import pytest
  import torch
  from torch.autograd import gradcheck
  import kornia.geometry.epipolar
  from kornia.testing import assert_close
label_desc: Use image node_id 5 for calling the TestScaleIntrinsics obj's underlying member method code with example usage: obj.test_gradcheck(device) without return types