code: def test_structural_element(self, device, dtype):
      tensor = torch.tensor(
          [[0.5, 1.0, 0.3], [0.7, 0.3, 0.8], [0.4, 0.9, 0.2]],
          device=device,
          dtype=dtype,
      )[None, None, :, :]
      structural_element = torch.tensor(
          [[-1.0, 0.0, -1.0], [0.0, 0.0, 0.0], [-1.0, 0.0, -1.0]],
          device=device,
          dtype=dtype,
      )
      expected = torch.tensor(
          [[0.5, 0.3, 0.3], [0.3, 0.3, 0.2], [0.4, 0.2, 0.2]],
          device=device,
          dtype=dtype,
      )[None, None, :, :]
      assert_close(
          erosion(
              tensor,
              torch.ones_like(structural_element),
              structuring_element=structural_element,
          ),
          expected,
          atol=1e-4,
          rtol=1e-4,
      )
      assert_close(
          erosion(
              tensor,
              torch.ones_like(structural_element),
              structuring_element=structural_element,
              engine="convolution",
          ),
          expected,
          atol=1e-3,
          rtol=1e-3,
      )
  
file_path: kornia/test/morphology/test_erosion.py
imports: import pytest
  import torch
  from torch.autograd import gradcheck
  from kornia.morphology import erosion
  from kornia.testing import assert_close
label_desc: Use image node_id 4 for calling the TestErode obj's underlying member method code with example usage: obj.test_structural_element(device, dtype) without return types