code: def test_result_grid_no_checkpoint(ray_start_2_cpus):
      def f(config):
          pass
  
      analysis = tune.run(f)
      result_grid = ResultGrid(analysis)
      result = result_grid[0]
      assert result.checkpoint is None
  
file_path: ray/python/ray/tune/tests/test_result_grid.py
imports: import pytest
  import ray
  from ray import train, tune
  from ray.train import Checkpoint, Result
  from ray.tune.result_grid import ResultGrid
  from ray.train.tests.util import create_dict_checkpoint, load_dict_checkpoint
label_desc: Use image node_id 3 for calling a global function with example usage: test_result_grid_no_checkpoint(ray_start_2_cpus) without return types