class_docstr: Basic in-memory dict-based object for saving Task Records.
  
  This is the first object to present the DB interface
  for logging tasks out of memory.
  
  The interface is based on MongoDB, so adding a MongoDB
  backend should be straightforward.
docstr: Add a new Task Record, by msg_id.
docstr_tok: ["Add","a","new","Task","Record",",","by","msg_id","."]
code: def add_record(self, msg_id, rec):
      """Add a new Task Record, by msg_id."""
      if msg_id in self._records:
          raise KeyError("Already have msg_id %r" % (msg_id))
      self._check_dates(rec)
      self._records[msg_id] = rec
      self._add_bytes(rec)
      self._maybe_cull()
  
imports: import copy
  from copy import deepcopy
  from datetime import datetime
  from traitlets import Dict, Float, Integer, Unicode
  from traitlets.config.configurable import LoggingConfigurable
  from ..util import ensure_timezone
label_desc: Use image node_id 9 for calling the DictDB obj's underlying member method code with example usage: obj.add_record(msg_id, rec) without return types