class_docstr: A property accepting a value of some other type while having undefined default. 
code: def __init__(
      self,
      type_param: TypeOrInst[Property[T]],
      *,
      default: Init[T] = Undefined,
      help: str | None = None,
  ) -> None:
      super().__init__(type_param, default=default, help=help)
  
file_path: bokeh/src/bokeh/core/property/required.py
imports: from __future__ import annotations
  import logging
  from typing import Any, TypeVar
  from ._sphinx import property_link, register_type_link, type_link
  from .bases import Init, Property, SingleParameterizedProperty, TypeOrInst
  from .singletons import Undefined
label_desc: Use image node_id 1 to create a new Required object from inherited base classes: SingleParameterizedProperty with example: obj = Required(type_param)