code: def close() -> None:
      global _context
      global train
  
      if _context is not None:
          _context.close()
  
      _context = None
      core_v2.train = None
  
file_path: determined/harness/determined/experimental/core_v2/_core_v2.py
imports: import atexit
  import dataclasses
  import logging
  import uuid
  from typing import Any, Dict, List, Optional, Union
  import determined
  from determined import core, experimental
  from determined.common import util
  from determined.experimental import core_v2
label_desc: Use image node_id 5 for calling a global function with example usage: close() without return types