code: def test_callback_list(self) -> None:
      X, y = tm.data.get_california_housing()
      m = xgb.DMatrix(X, y)
      callbacks = [xgb.callback.EarlyStopping(rounds=10)]
      for i in range(4):
          xgb.train(
              {"objective": "reg:squarederror", "eval_metric": "rmse"},
              m,
              evals=[(m, "Train")],
              num_boost_round=1,
              verbose_eval=True,
              callbacks=callbacks,
          )
      assert len(callbacks) == 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 16 for calling the TestCallbacks obj's underlying member method code with example usage: obj.test_callback_list() without return types