code: def _get_column_value(self, column_name):
      return self.tree_to_dataframe[column_name].to_numpy()
  
imports: import json
  import math
  from collections import defaultdict
  from typing import List, Mapping
  import numpy
  from dtreeviz.models.shadow_decision_tree import VisualisationNotYetSupportedError
  from dtreeviz.models.shadow_decision_tree import ShadowDecTree
  from dtreeviz import utils
  import xgboost
  from xgboost.core import Booster
label_desc: Use image node_id 17 for calling the ShadowXGBDTree obj's underlying member method code with example usage: obj._get_column_value(column_name) and returns: self