code: def cancel(self, event=None):
      self.result = ""
      self.grab_release()
      self.destroy()
  
imports: from tkinter import Toplevel, Listbox, StringVar, TclError
  from tkinter.ttk import Frame, Button, Checkbutton, Entry, Label, Scrollbar
  from tkinter import messagebox
  from tkinter.simpledialog import _setup_dialog
  import string
  import sys
label_desc: Use image node_id 5 for calling the GetKeysWindow obj's underlying member method code with example usage: obj.cancel(event) without return types