code: def test_batch_shape(self, bs, device):
      inp = torch.ones(bs, 1, 15, 15).to(device)
      vm = VonMisesKernel(
          patch_size=15, coeffs=[0.38214156, 0.48090413]
      ).to(device)
      out = vm(inp)
      assert out.shape == (bs, 3, 15, 15)
  
imports: from math import pi
  import pytest
  import torch
  from torch.autograd import gradcheck
  import kornia.testing
  from kornia.feature.mkd import COEFFS, EmbedGradients, ExplicitSpacialEncoding, MKDDescriptor, MKDGradients, SimpleKD, VonMisesKernel, Whitening, get_grid_dict, get_kron_order, spatial_kernel_embedding
  from kornia.testing import assert_close
label_desc: Use image node_id 2 for calling the TestVonMisesKernel obj's underlying member method code with example usage: obj.test_batch_shape(bs, device) without return types