code: def test_force_two_dimensions():
      # Test with 2D array
      X = np.zeros((5, 5))
      X_reshaped = util.force_two_dimensions(X)
      assert X_reshaped.shape == (
          5,
          5,
      ), "The shape of 2D array should remain unchanged."
  
      # Test with 4D array
      X = np.zeros((5, 5, 5, 5))
      X_reshaped = util.force_two_dimensions(X)
      assert X_reshaped.shape == (
          5,
          125,
      ), "The shape of 4D array should be flattened to two dimensions."
  
      # Test with None input
      assert (
          util.force_two_dimensions(None) is None
      ), "None input should return None."
  
imports: from cleanlab.internal import util
  import numpy
  import pytest
  from cleanlab.internal.label_quality_utils import get_normalized_entropy
  from cleanlab.internal.multilabel_utils import int2onehot, onehot2int
  from cleanlab.internal.util import num_unique_classes, format_labels, get_missing_classes
  from cleanlab.internal.validation import assert_valid_class_labels
label_desc: Use image node_id 17 for calling a global function with example usage: test_force_two_dimensions() without return types