class_docstr: Module that calculates Difference-of-Gaussians blobs.
  
  .. image:: _static/img/dog_response_single.png
  
  See :func:`~kornia.feature.dog_response_single` for details.
code: def forward(
      self, input: Tensor, sigmas: Optional[Tensor] = None
  ) -> Tensor:
      return dog_response_single(input, self.sigma1, self.sigma2)
  
imports: from typing import Optional, Union
  import torch
  from kornia.core import Module, Tensor, tensor
  from kornia.core.check import KORNIA_CHECK_SHAPE
  from kornia.filters import gaussian_blur2d, spatial_gradient
label_desc: Use image node_id 3 for calling the BlobDoGSingle obj's underlying member method code with example usage: obj.forward(input, sigmas) and returns: dog_response_single