code: def test_eta_decay_leaf_output(
      self, tree_method: str, objective: str
  ) -> None:
      self.run_eta_decay_leaf_output(tree_method, objective)
  
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 14 for calling the TestCallbacks obj's underlying member method code with example usage: obj.test_eta_decay_leaf_output(tree_method, objective) without return types