class_docstr: A base class for sidebars using Text.
docstr: Hook for vertical scrolling for sub-classes to override.
docstr_tok: ["Hook","for","vertical","scrolling","for","sub-classes","to","override","."]
code: def yscroll_event(self, *args, **kwargs):
      """Hook for vertical scrolling for sub-classes to override."""
      raise NotImplementedError
  
imports: import contextlib
  import functools
  import itertools
  import tkinter
  from tkinter.font import Font
  from idlelib.config import idleConf
  from idlelib.delegator import Delegator
  from idlelib import macosx
label_desc: Use image node_id 8 for calling the BaseSideBar obj's underlying member method code with example usage: obj.yscroll_event() without return types