code: def test_exception(self):
      inpt = torch.rand(1, 1, 3, 3)
  
      with pytest.raises(Exception) as errinfo:
          box_blur(inpt, (1,))
      assert "2D Kernel size should have a length of 2." in str(errinfo)
  
file_path: kornia/test/filters/test_blur.py
imports: import pytest
  import torch
  from kornia.filters import BoxBlur, box_blur
  from kornia.testing import BaseTester, tensor_to_gradcheck_var
label_desc: Use image node_id 3 for calling the TestBoxBlur obj's underlying member method code with example usage: obj.test_exception() without return types