code: def flip(self, event=None):
      if self.state == "expanded":
          self.collapse()
      else:
          self.expand()
      self.item.OnDoubleClick()
      return "break"
  
imports: import os
  from tkinter import *
  from tkinter.ttk import Frame, Scrollbar
  from idlelib.config import idleConf
  from idlelib import zoomheight
label_desc: Use image node_id 8 for calling the TreeNode obj's underlying member method code with example usage: obj.flip(event) and returns: str