class_docstr: The debugger interface.
  
  This class handles the drawing of the debugger window and
  the interactions with the underlying debugger session.
code: def show_stack(self):
      if not self.stackviewer and self.vstack.get():
          self.stackviewer = sv = StackViewer(
              self.fstack, self.flist, self
          )
          if self.frame:
              stack, i = self.idb.get_stack(self.frame, None)
              sv.load_stack(stack, i)
      else:
          sv = self.stackviewer
          if sv and not self.vstack.get():
              self.stackviewer = None
              sv.close()
          self.fstack["height"] = 1
  
imports: import bdb
  import os
  from tkinter import *
  from tkinter.ttk import Frame, Scrollbar
  from idlelib import macosx
  from idlelib.scrolledlist import ScrolledList
  from idlelib.window import ListedToplevel
label_desc: Use image node_id 14 for calling the Debugger obj's underlying member method code with example usage: obj.show_stack() without return types