scroll 2 listboxes in paned windows

scrolled_lists.py

#! /usr/bin/env python

from Tkinter import *
from ttk import *

import calendar

root = Tk()

master = Frame(root)
master.pack(expand=YES, fill=BOTH)

panels = PanedWindow(master, orient=HORIZONTAL)
panels.pack(expand=YES, fill=BOTH)

panel1 = Frame(panels)
panel1.pack(expand=YES, fill=BOTH)

list1 = Listbox(panel1)
list1.pack(side=LEFT, expand=YES, fill=BOTH)
for m in calendar.month_name:
    list1.insert(END, m)
for d in calendar.day_name:
    list1.insert(END, d)

panel2 = Frame(panels)
panel2.pack(expand=YES, fill=BOTH)

list2 = Listbox(panel2)
list2.pack(side=LEFT, expand=YES, fill=BOTH)
for m in calendar.month_name:
    list2.insert(END, m)
for d in calendar.day_name:
    list2.insert(END, d)

scroll = Scrollbar(panel2, orient=VERTICAL)
scroll.pack(side=RIGHT, fill=Y)

list1.config(yscrollcommand=scroll.set)
list2.config(yscrollcommand=scroll.set)
scroll.config(command=lambda *args: onScroll([list1, list2], *args))

Label(master, text='scrolled lists').pack(side=LEFT, fill=BOTH)
Button(master, text='quit', command=master.quit).pack(side=RIGHT, fill=BOTH)

panels.add(panel1)
panels.add(panel2)

def onScroll(lists, *args):
    for l in lists:
        l.yview(*args)

if __name__ == '__main__':
    master.mainloop()