code: def test_early_stopping_continuation(self):
      from sklearn.datasets import load_breast_cancer
  
      X, y = load_breast_cancer(return_X_y=True)
  
      early_stopping_rounds = 5
      early_stop = xgb.callback.EarlyStopping(
          rounds=early_stopping_rounds, save_best=True
      )
      cls = xgb.XGBClassifier(
          eval_metric=tm.eval_error_metric_skl, callbacks=[early_stop]
      )
      cls.fit(X, y, eval_set=[(X, y)])
  
      booster = cls.get_booster()
      assert booster.num_boosted_rounds() == booster.best_iteration + 1
  
      with tempfile.TemporaryDirectory() as tmpdir:
          path = os.path.join(tmpdir, "model.json")
          cls.save_model(path)
          cls = xgb.XGBClassifier()
          cls.load_model(path)
          assert cls._Booster is not None
          early_stopping_rounds = 3
          cls.set_params(
              eval_metric=tm.eval_error_metric_skl,
              early_stopping_rounds=early_stopping_rounds,
          )
          cls.fit(X, y, eval_set=[(X, y)])
          booster = cls.get_booster()
          assert (
              booster.num_boosted_rounds()
              == booster.best_iteration + early_stopping_rounds + 1
          )
  
imports: import json
  import os
  import tempfile
  from typing import Union
  import pytest
  import xgboost
  from xgboost import testing
label_desc: Use image node_id 10 for calling the TestCallbacks obj's underlying member method code with example usage: obj.test_early_stopping_continuation() without return types