如何在Tkinter中移除级联菜单的边框？

menu = tkinter.Menu(root)

submenu = tkinter.Menu(menu, tearoff=0)
menu.add_cascade(label="Options", menu=submenu)

submenu.config(borderwidth=0, activeborderwidth=0)

submenu.add_command(label="Option 1", command=option1)
submenu.add_command(label="Option 2", command=option2)

import tkinter

def option1():
    print("Option 1 selected")

def option2():
    print("Option 2 selected")

root = tkinter.Tk()

menu = tkinter.Menu(root)
submenu = tkinter.Menu(menu, tearoff=0)
submenu.config(borderwidth=0, activeborderwidth=0)
menu.add_cascade(label="Options", menu=submenu)
submenu.add_command(label="Option 1", command=option1)
submenu.add_command(label="Option 2", command=option2)

root.config(menu=menu)
root.mainloop()