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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 msgbox(msg="(Your message goes here)", title=" ", ok_button="OK", image=None, root=None):
 """ Display a message box :param str msg: the msg to be displayed :param str title: the window title :param str ok_button: text to show in the button :param str image: Filename of image to display :param tk_widget root: Top-level Tk widget :return: the text of the ok_button """

    if not isinstance(ok_button, ut.str):
        raise AssertionError(
            "The 'ok_button' argument to msgbox must be a string.")

    return bb.buttonbox(msg=msg,
                        title=title,
                        choices=[ok_button],
                        image=image,
                        root=root,
                        default_choice=ok_button,
                        cancel_choice=ok_button)