code: def test_get_features(spark_dtree):
      assert np.array_equal(
          spark_dtree.get_features(),
          np.array(
              [
                  1,
                  3,
                  4,
                  -1,
                  -1,
                  -1,
                  0,
                  3,
                  0,
                  -1,
                  -1,
                  -1,
                  6,
                  2,
                  -1,
                  -1,
                  -1,
              ]
          ),
      ), "Feature indexes should be [1, 3, 4, -1, -1, -1, 0, 3, 0, -1, -1, -1, 6, 2, -1, -1, -1]"
  
imports: import numpy
  import pyspark
  import pytest
  from pyspark.ml.classification import DecisionTreeClassificationModel
  from pyspark.sql import SparkSession
  from dtreeviz.models.spark_decision_tree import ShadowSparkTree
label_desc: Use image node_id 8 for calling a global function with example usage: test_get_features(spark_dtree) without return types