code: def test_dump_callback(tmp_path: Path) -> None:
      filepath = tmp_path / "pickle.pkl"
      optimizer = optimizerlib.OnePlusOne(parametrization=2, budget=32)
      optimizer.register_callback(
          "tell", ng.callbacks.OptimizerDump(filepath)
      )
      cand = optimizer.ask()
      assert not filepath.exists()
      optimizer.tell(cand, 0)
      assert filepath.exists()
  
imports: import time
  from pathlib import Path
  import logging
  import os
  import numpy
  import nevergrad
  import nevergrad.common.typing
  from .None import optimizerlib
  from .None import callbacks
label_desc: Use image node_id 5 for calling a global function with example usage: test_dump_callback(tmp_path) without return types