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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def ok(self, event=None):
 """Function called when OK-button is clicked. This method calls check_input(), and if that returns ok it calls execute(), and then destroys the dialog. """


        if not self.check_input():
            self.initial_focus.focus_set()
            return

        self.withdraw()
        self.update_idletasks()

        try:
            self.execute()
        finally:
            self.cancel()