test.py

import tkinter
from tkinter import *


class Example(Frame):
    def __init__(self, root):
        Frame.__init__(self, root)

        self.menubar = Menu()
        self.test1Menu = Menu()
        self.test2Menu = Menu()
        self.menubar.add_cascade(label="Test1", menu=self.test1Menu)
        self.menubar.add_cascade(label="Test2", menu=self.test2Menu)

        self.test1Menu.add_command(
            label="Enable Test2", command=self.enable_menu)
        self.test1Menu.add_command(
            label="Disable Test2", command=self.disable_menu)
        self.test2Menu.add_command(label="One")
        self.test2Menu.add_command(label="Two")
        self.test2Menu.add_command(label="Three")
        self.test2Menu.add_separator()
        self.test2Menu.add_command(label="Four")
        self.test2Menu.add_command(label="Five")

        root.configure(menu=self.menubar)

    def enable_menu(self):
        self.menubar.entryconfig("Test2", state="normal")

    def disable_menu(self):
        self.menubar.entryconfig("Test2", state="disabled")


if __name__ == "__main__":
    root = Tk()
    root.geometry("500x500")
    app = Example(root)
    app.pack(fill="both", expand=True)
    root.mainloop()