code: def test_categorical_1(self):
      sf = tc.SFrame(
          {
              "cat1": ["1", "1", "2", "2", "2"] * 100,
              "cat2": ["1", "3", "3", "1", "1"] * 100,
          }
      )
      self._run_test(sf, 4)
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import unittest
  import turicreate
  import math
  import uuid
  import random
  import copy
  from turicreate.toolkits import evaluation
  from turicreate.toolkits._main import ToolkitError
  import shutil
  import numpy
  from array import array
label_desc: Use image node_id 2 for calling the TreeExtractFeaturesTest obj's underlying member method code with example usage: obj.test_categorical_1() without return types