class_docstr: Test functions that display files.
  
  While somewhat redundant with gui-based test_file_dialog,
  these unit tests run on all buildbots, not just a few.
class_docstr_tok: ["Test","functions","that","display","files",".","While","somewhat","redundant","with","gui-based","test_file_dialog",",","these","unit","tests","run","on","all","buildbots",",","not","just","a","few","."]
code: def tearDownClass(cls):
      textview.showerror = cls.orig_error
      textview.view_text = cls.orig_view
  
imports: from idlelib import help_about
  import unittest
  from test.support import requires, findfile
  from tkinter import Tk, TclError
  from idlelib.idle_test.mock_idle import Func
  from idlelib.idle_test.mock_tk import Mbox_func
  from idlelib import textview
  import os.path
  from platform import python_version
label_desc: Use image node_id 2 for calling the DisplayFileTest obj's underlying member method code with example usage: obj.tearDownClass(cls) without return types