class_docstr: The user-facing class that provides metric storage functionalities.
  
  In the future we may add support for storing / logging other types of data if needed.
docstr: Returns:
      dict[name -> HistoryBuffer]: the HistoryBuffer for all scalars
docstr_tok: ["Returns",":","dict","[","name","-",">","HistoryBuffer","]",":","the","HistoryBuffer","for","all","scalars"]
code: def histories(self):
      """
      Returns:
          dict[name -> HistoryBuffer]: the HistoryBuffer for all scalars
      """
      return self._history
  
imports: import datetime
  import json
  import logging
  import os
  import time
  from collections import defaultdict
  from contextlib import contextmanager
  from functools import cached_property
  from typing import Optional
  import torch
  from fvcore.common.history_buffer import HistoryBuffer
  from detectron2.utils.file_io import PathManager
label_desc: Use image node_id 7 for calling the EventStorage obj's underlying member method code with example usage: obj.histories() and returns: self