code: def __init__(self, *args, **kw):
      super().__init__(*args, **kw)
      self._document = None
      self._temp_document = None
  
file_path: bokeh/src/bokeh/model/util.py
imports: from __future__ import annotations
  import logging
  from typing import TYPE_CHECKING, Any, Callable
  from ..core.has_props import HasProps, Qualified
  from ..util.dataclasses import entries, is_dataclass
label_desc: Use image node_id 1 to create a new HasDocumentRef object  with example: obj = HasDocumentRef()