class_docstr: A blackhole db backend that actually stores no information.
  
  Provides the full DB interface, but raises KeyErrors on any
  method that tries to access the records.  This can be used to
  minimize the memory footprint of the Hub when its record-keeping
  functionality is not required.
code: def add_record(self, msg_id, record):
      pass
  
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 1 for calling the NoDB obj's underlying member method code with example usage: obj.add_record(msg_id, record) without return types