code: def test_statistics(self, data_issues):
      stats = data_issues.statistics
  
      assert stats == data_issues.info["statistics"]
      assert (
          stats["num_examples"] == 3
      ), f"Incorrect number of examples: {stats['num_examples']}"
      assert stats["class_names"] == [
          "A",
          "B",
      ], f"Incorrect class names: {stats['class_names']}"
      assert (
          stats["num_classes"] == 2
      ), f"Incorrect number of classes: {stats['num_classes']}"
      assert stats["multi_label"] is False
      assert (
          stats["health_score"] is None
      ), f"Health score should initially be None, but is {stats['health_score']}"
  
file_path: cleanlab/tests/datalab/test_data_issues.py
imports: import pytest
  from cleanlab.datalab.internal.data import Data
  from cleanlab.datalab.internal.data_issues import DataIssues, _ClassificationInfoStrategy
label_desc: Use image node_id 3 for calling the TestDataIssues obj's underlying member method code with example usage: obj.test_statistics(data_issues) without return types