class_docstr: This tricky little class is used to make sure that modules under test
  will be reloaded the next time they are imported.
class_docstr_tok: ["This","tricky","little","class","is","used","to","make","sure","that","modules","under","test","will","be","reloaded","the","next","time","they","are","imported","."]
code: def rollbackImports(self):
      for modname in sys.modules.copy().keys():
          if not modname in self.previousModules:
              # Force reload when modname next imported
              del sys.modules[modname]
  
imports: import sys
  import traceback
  import unittest
  import tkinter
  from tkinter import messagebox
  from tkinter import filedialog
  from tkinter import simpledialog
label_desc: Use image node_id 2 for calling the RollbackImporter obj's underlying member method code with example usage: obj.rollbackImports() without return types