code: def __init__(self, ext_name, device_id):
      super(CpuTimerCallback, self).__init__()
  
      self.results = OrderedDict()
      self.device_id = str(device_id)
      self.ext_module = import_extension_module(ext_name)
      self.key_to_times = OrderedDict()
  
imports: from __future__ import absolute_import
  import csv
  import os
  import time
  from collections import OrderedDict
  from contextlib import contextmanager
  from importlib import import_module
  import numpy
  from nnabla.ext_utils import import_extension_module
  from .base import FunctionHookCallbackBase
label_desc: Use image node_id 1 to create a new CpuTimerCallback object from inherited base classes: FunctionHookCallbackBase with example: obj = CpuTimerCallback(ext_name, device_id)