Python，Tkinter - DropDown菜单

Question

我只是想创建一个简单的下拉菜单，并在单击一个命令时将您引导到特定的框架。我知道我做错了什么，但我不知道它是什么。任何人都可以指导我或给我一个例子吗？

    # Redirects to a specific frame
def GoFrame(goFrameNow):
    FAQ.grid_forget()
    GoFrameNow.grid()

# Core knowledge content and design after login successfull (myGUI being main root)    
def Core():
    myGUI.withdraw()
    NewRoot = Toplevel(myGUI,
                       bg="powderblue")
    NewRoot.geometry('800x500')
    NewRoot.resizable(width=False, height=False)
    # DropDown Menu being created
    mainMenu = Menu(NewRoot)
    NewRoot.config(menu=mainMenu)
    CoreContentMenu = Menu(mainMenu)
    mainMenu.add_cascade(label="Support", menu=CoreContentMenu)
    CoreContentMenu.add_command=Label("FAQ", command=lambda: GoFrame(FAQ))

# Creates FAQ frame to test
FAQ = Frame(Core)
Label(FAQ, text="Testing").grid(row=0, column=0, columnspan=2)