code: def setUp(self):
      self.redir = WidgetRedirector(self.text)
      self.func = Func()
      self.orig_insert = self.redir.register("insert", self.func)
      self.text.insert("insert", "asdf")
  
imports: from idlelib.redirector import WidgetRedirector
  import unittest
  from test.support import requires
  from tkinter import Tk, Text, TclError
  from idlelib.idle_test.mock_idle import Func
label_desc: Use image node_id 3 for calling the WidgetRedirectorTest obj's underlying member method code with example usage: obj.setUp() without return types