code: def classes(self) -> np.ndarray:
      if self.is_classifier():
          return np.unique(self.y_train)
  
imports: from abc import ABC
  from collections import defaultdict
  from typing import List, Mapping
  import numpy
  import pyspark
  from dtreeviz.models.shadow_decision_tree import ShadowDecTree
  from dtreeviz.utils import criterion_remapping
  from pyspark.ml.classification import DecisionTreeClassificationModel
  from pyspark.ml.regression import DecisionTreeRegressionModel
label_desc: Use image node_id 12 for calling the ShadowSparkTree obj's underlying member method code with example usage: obj.classes() and returns: np