code: def test_samples(self):
      testing_dir = os.path.join(
          os.path.dirname(os.path.realpath(__file__)), "testing_data"
      )
      keys = "image"
      xforms = Compose(
          [
              LoadImaged(keys=keys),
              EnsureChannelFirstd(keys=keys),
              ScaleIntensityd(keys=keys),
              RandSpatialCropSamplesd(
                  keys=keys,
                  roi_size=(8, 8, 5),
                  random_size=True,
                  num_samples=10,
              ),
          ]
      )
      image_path = os.path.join(testing_dir, "anatomical.nii")
      xforms.set_random_state(0)
      ims = xforms({keys: image_path})
      fig, mat = matshow3d(
          [im[keys] for im in ims],
          title=f"testing {keys}",
          figsize=(2, 2),
          frames_per_row=5,
          every_n=2,
          show=False,
      )
      self.assertTrue(mat.dtype == np.float32)
  
      with tempfile.TemporaryDirectory() as tempdir:
          tempimg = f"{tempdir}/matshow3d_patch_test.png"
          fig.savefig(tempimg)
          comp = compare_images(
              f"{testing_dir}/matshow3d_patch_test.png",
              tempimg,
              5e-2,
              in_decorator=True,
          )
          if comp:
              print("not none comp: ", comp)  # matplotlib 3.2.2
              np.testing.assert_allclose(
                  comp["rms"], 30.786983, atol=1e-3, rtol=1e-3
              )
          else:
              self.assertIsNone(comp, f"value of comp={comp}")
  
file_path: MONAI/tests/test_matshow3d.py
imports: from __future__ import annotations
  import os
  import tempfile
  import unittest
  import numpy
  from monai.transforms import Compose, EnsureChannelFirstd, LoadImaged, RandSpatialCropSamplesd, RepeatChanneld, ScaleIntensityd
  from monai.utils import optional_import
  from monai.visualize.utils import matshow3d
  from tests.utils import SkipIfNoModule
label_desc: Use image node_id 2 for calling the TestMatshow3d obj's underlying member method code with example usage: obj.test_samples() without return types