code: def test_theils_u_matrix(
      theils_u_matrix_input, nan_strategy, nan_replace_value
  ):
      """Test matrix version of metric works as expected."""
      tm_score = theils_u_matrix(
          theils_u_matrix_input, nan_strategy, nan_replace_value
      )
      reference_score = _dython_theils_u_matrix(
          theils_u_matrix_input, nan_strategy, nan_replace_value
      )
      assert torch.allclose(tm_score, reference_score, atol=1e-6)
  
file_path: torchmetrics/tests/unittests/nominal/test_theils_u.py
imports: import itertools
  import operator
  from functools import partial
  import pytest
  import torch
  from dython.nominal import theils_u
  from lightning_utilities.core.imports import compare_version
  from torchmetrics.functional.nominal.theils_u import theils_u, theils_u_matrix
  from torchmetrics.nominal import TheilsU
  from unittests import BATCH_SIZE, NUM_BATCHES, _Input
  from unittests.helpers.testers import MetricTester
label_desc: Use image node_id 4 for calling a global function with example usage: test_theils_u_matrix(theils_u_matrix_input, nan_strategy, nan_replace_value) without return types