import tkinter as tk

win=tk.Tk()

win.title('主窗口')

win.geometry('350x250')

def click():

    win2=tk.Toplevel(win)

    win2.title('小窗口1')

    win2.geometry('250x150')

    label=tk.Label(win2,text='这是一个小窗口',bg='yellow',font=('Arias',20))

    label.pack()

def click2():

    win3=tk.Toplevel(win)

    win3.title('小窗口2')

    win3.geometry('250x150')

    label=tk.Label(win3,text='这是一个小窗口',bg='yellow',font=('Arias',20))

    label.pack()

button=tk.Button(win,text='小窗口1',font=('Arias',12),bg='green',command=click)

button2=tk.Button(win,text='小窗口2',font=('Arias',12),bg='green',command=click2)

button.pack()

button2.pack()

win.mainloop()