code: def test_eta_decay_leaf_output(self, objective) -> None:
      self.cpu_test_cb.run_eta_decay_leaf_output("gpu_hist", objective)
  
file_path: xgboost/tests/python-gpu/test_gpu_basic_models.py
imports: import os
  import sys
  import numpy
  import pytest
  import xgboost
  from xgboost import testing
  import test_basic_models
  import test_callback
label_desc: Use image node_id 4 for calling the TestGPUBasicModels obj's underlying member method code with example usage: obj.test_eta_decay_leaf_output(objective) without return types