code: def _add_tz(obj):
      if isinstance(obj, datetime):
          obj = ensure_timezone(obj)
      return obj
  
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 a global function with example usage: _add_tz(obj) and returns: obj