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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 insertMenuBefore(self, before_menu, new_menu):
 """ Insert a menu after another menu in the menubar @type: before_menu QMenu instance or title string of menu @param before_menu: menu which should be after the newly inserted menu @rtype: QAction instance @return: action for inserted menu """

        if isinstance(before_menu, string_types):
            before_menu = self.findMenu(before_menu)
        before_action = self.actionForMenu(before_menu)
        # I have no clue why QMenuBar::insertMenu only allows
        # to insert before another menu and not after a menu...
        new_action = self.insertMenu(before_action, new_menu)
        return new_action