code: def _test_regression_model(
      self, train, test, rmse_threshold, target="label"
  ):
      # create
      model = tc.decision_tree_regression.create(
          train, target=target, validation_set=test, **self.param
      )
      # predict
      pred = model.predict(test)
      pred_lst = model.predict(list(test))
      rmse = evaluation.rmse(pred, test[target])
      self.assertLess(rmse, rmse_threshold)
  
      # evaluate
      rmse_eval = model.evaluate(test, metric="rmse")["rmse"]
      self.assertTrue(rmse_eval < rmse_threshold)
      self.assertAlmostEqual(rmse_eval, rmse, delta=1e-2)
  
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
  import os
label_desc: Use image node_id 13 for calling the DecisionTreeRegressionTest obj's underlying member method code with example usage: obj._test_regression_model(train, test, rmse_threshold, target) without return types