class_docstr: Access the history database without adding to it.
  
  This is intended for use by standalone history tools. IPython shells use
  HistoryManager, below, which is a subclass of this.
class_docstr_tok: ["Access","the","history","database","without","adding","to","it",".","This","is","intended","for","use","by","standalone","history","tools",".","IPython","shells","use","HistoryManager",",","below",",","which","is","a","subclass","of","this","."]
docstr: Overridden by HistoryManager to dump the cache before certain
  database lookups.
docstr_tok: ["Overridden","by","HistoryManager","to","dump","the","cache","before","certain","database","lookups","."]
code: def writeout_cache(self):
      """Overridden by HistoryManager to dump the cache before certain
      database lookups."""
      pass
  
imports: import atexit
  import datetime
  from pathlib import Path
  import re
  import sqlite3
  import threading
  from traitlets.config.configurable import LoggingConfigurable
  from decorator import decorator
  from IPython.utils.decorators import undoc
  from IPython.paths import locate_profile
  from traitlets import Any, Bool, Dict, Instance, Integer, List, Unicode, Union, TraitError, default, observe
label_desc: Use image node_id 6 for calling the HistoryAccessor obj's underlying member method code with example usage: obj.writeout_cache() without return types