code: def test_shape(self, device, dtype, kernel):
      sample = torch.ones(32, 32, device=device, dtype=dtype)
      hist, pdf = TestImageHistogram2d.fcn(
          sample, 0.0, 1.0, 256, kernel=kernel
      )
      assert hist.shape == (256,)
      assert pdf.shape == (256,)
  
imports: import pytest
  import torch
  from packaging import version
  from torch.autograd import gradcheck
  import kornia
  import kornia.testing
  from kornia.testing import assert_close
label_desc: Use image node_id 1 for calling the TestImageHistogram2d obj's underlying member method code with example usage: obj.test_shape(device, dtype, kernel) without return types