code: def test_samplewise_confusion_matrix_merge(self):
      y_pred = ["dog", "cat", "cat"]
      y_true = ["dog", "cat", "bird"]
      confusion_matrix = _classification.SamplewiseConfusionMatrixAggFn(
          metrics=(ConfusionMatrixMetric.PRECISION,),
          input_type=InputType.MULTICLASS,
      )
      acc = confusion_matrix.add_inputs(
          confusion_matrix.create_accumulator(), y_true, y_pred
      )
      actual = confusion_matrix.add_inputs(acc, y_true, y_pred)
      expected = {"precision": _classification.MeanState(4, 6)}
      self.assertDictEqual(expected, actual)
  
imports: from absl.testing import absltest
  from absl.testing import parameterized
  import numpy
  from tensorflow_model_analysis.experimental.metrics.aggregates import _classification
label_desc: Use image node_id 9 for calling the ClassificationTest obj's underlying member method code with example usage: obj.test_samplewise_confusion_matrix_merge() without return types