def my_add_fn():
print "SUM:%s"%sum(map(int,raw_input("Enter 2 numbers seperated by a space").split()))
def my_quit_fn():
raise SystemExit
def invalid():
print "INVALID CHOICE!"
menu = {"1":("Sum",my_add_fn),
"2":("Quit",my_quit_fn)
}
for key in sorted(menu.keys()):
print key+":" + menu[key][0]
ans = raw_input("Make A Choice")
menu.get(ans,[None,invalid])[1]()