code: def test_decision_tree_multiclass_simple(self):
      for code_string in ["nn"]:
          train, test = self.generate_data(
              "multiclass", 100, code_string
          )
          model = tc.decision_tree_classifier.create(
              train, "target", validation_set=None, max_depth=3
          )
          model.evaluate(
              test
          )  # Previous classifier -- this caused errors.
          self._test_coreml_export(model, test, False)
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import unittest
  import tempfile
  import turicreate
  import math
  import uuid
  import random
  import copy
  from turicreate.toolkits import evaluation
  from turicreate.toolkits._main import ToolkitError
  from turicreate.toolkits._internal_utils import _mac_ver
  import shutil
  import numpy
  import sys
  import platform
  import array
  import os
  import pytest
label_desc: Use image node_id 19 for calling the CoreMLExportTest obj's underlying member method code with example usage: obj.test_decision_tree_multiclass_simple() without return types