code: def _canonicalize(self, parents):
      if "/" not in self.msg:
          self.msg = parents[0].msg + "/" + self.msg
      super()._canonicalize(parents)
  
file_path: nni/test/ut/experiment/test_config_base.py
imports: from copy import deepcopy
  from dataclasses import dataclass
  from typing import Dict, List, Optional, Union
  from nni.experiment.config.base import ConfigBase
  from nni.experiment.config.utils import diff
label_desc: Use image node_id 1 for calling the Child obj's underlying member method code with example usage: obj._canonicalize(parents) without return types