code: def uplift_tree_string(decisionTree, x_names):
      """
      Convert the tree to string for print.
  
      Args
      ----
  
      decisionTree : object
          object of DecisionTree class
  
      x_names : list
          List of feature names
  
      Returns
      -------
      A string representation of the tree.
      """
  
      # Column Heading
      dcHeadings = {}
      for i, szY in enumerate(x_names + ["treatment_group_key"]):
          szCol = "Column %d" % i
          dcHeadings[szCol] = str(szY)
  
      def toString(decisionTree, indent=""):
          if decisionTree.results is not None:  # leaf node
              return str(decisionTree.results)
          else:
              szCol = "Column %s" % decisionTree.col
              if szCol in dcHeadings:
                  szCol = dcHeadings[szCol]
              if isinstance(decisionTree.value, int) or isinstance(
                  decisionTree.value, float
              ):
                  decision = "%s >= %s?" % (szCol, decisionTree.value)
              else:
                  decision = "%s == %s?" % (szCol, decisionTree.value)
              trueBranch = (
                  indent
                  + "yes -> "
                  + toString(decisionTree.trueBranch, indent + "\t\t")
              )
              falseBranch = (
                  indent
                  + "no  -> "
                  + toString(decisionTree.falseBranch, indent + "\t\t")
              )
              return decision + "\n" + trueBranch + "\n" + falseBranch
  
      print(toString(decisionTree))
  
imports: from collections import defaultdict
  import matplotlib.pyplot
  import numpy
  import pydotplus
  import seaborn
  from sklearn.tree import _tree
  from sklearn.tree._export import _MPLTreeExporter, _color_brew
  from sklearn.utils.validation import check_is_fitted
  from .None import CausalTreeRegressor
  from .utils import get_tree_leaves_mask
label_desc: Use image node_id 1 for calling a global function with example usage: uplift_tree_string(decisionTree, x_names) and returns: str, unknown