code: def test_gpu_hist_depthwise():
      params = {
          "tree_method": "gpu_hist",
          "grow_policy": "depthwise",
          "monotone_constraints": "(1, -1)",
      }
      model = xgb.train(params, tmc.training_dset)
      tmc.is_correctly_constrained(model)
  
file_path: xgboost/tests/python-gpu/test_monotonic_constraints.py
imports: import sys
  import numpy
  import pytest
  import xgboost
  from xgboost import testing
  import test_monotone_constraints
label_desc: Use image node_id 5 for calling a global function with example usage: test_gpu_hist_depthwise() without return types