Get menu label when click on a command in Tkinter Menu

tkinter_menu.py

from tkinter import *
from tkinter import ttk


def test(sheet_name, material):
    print(sheet_name)
    print(material)


class material_menu():
    def __init__(self, name):
        menubutton = ttk.Menubutton(text=name)
        menubutton.grid(column=0, row=0, sticky=(N, S, E, W))
        menubutton.menu = Menu(menubutton)
        menubutton["menu"] = menubutton.menu
        dict = {}
        for sheet_name in ["Menu A", "Menu B", "MenuC"]:
            dict[sheet_name] = Menu(menubutton.menu)
            menubutton.menu.add_cascade(label=sheet_name, menu=dict[sheet_name])
            for material in ["item1", "item2", "item3"]:
                dict[sheet_name].add_command(label=material, command=lambda sheet_name=sheet_name, material=material: test(sheet_name, material))
if __name__ == "__main__":
    win = Tk()
    material_menu("Menubutton")
    win.mainloop()