code: def test3d_gaussian(self):
      set_determinism(0)
      preds = torch.abs(torch.randn(1, 1, 64, 64, 64))
      target = torch.abs(torch.randn(1, 1, 64, 64, 64))
      preds = preds / preds.max()
      target = target / target.max()
  
      metric = MultiScaleSSIMMetric(
          spatial_dims=3,
          data_range=1.0,
          kernel_type="gaussian",
          weights=[0.5, 0.5],
      )
      metric(preds, target)
      result = metric.aggregate()
      expected_value = 0.061796
      self.assertTrue(expected_value - result.item() < 0.000001)
  
file_path: MONAI/tests/test_compute_multiscalessim_metric.py
imports: from __future__ import annotations
  import unittest
  import torch
  from monai.metrics import MultiScaleSSIMMetric
  from monai.utils import set_determinism
label_desc: Use image node_id 3 for calling the TestMultiScaleSSIMMetric obj's underlying member method code with example usage: obj.test3d_gaussian() without return types