class_docstr: A ``PropertyDescriptor`` for Bokeh |DataSpec| properties that serialize to
  field/value dictionaries.
class_docstr_tok: ["A","``","PropertyDescriptor","``","for","Bokeh","|DataSpec|","properties","that","serialize","to","field\/value","dictionaries","."]
code: def get_value(self, obj: HasProps) -> Any:
      """ """
      return self.property.to_serializable(
          obj, self.name, getattr(obj, self.name)
      )
  
imports: from __future__ import annotations
  import logging
  from copy import copy
  from types import FunctionType
  from typing import TYPE_CHECKING, Any, Callable, Generic, TypeVar
  from ...util.deprecation import deprecated
  from .singletons import Undefined
  from .wrappers import PropertyValueColumnData, PropertyValueContainer
label_desc: Use image node_id 1 for calling the DataSpecPropertyDescriptor obj's underlying member method code with example usage: obj.get_value(obj) and returns: self