tkinter combox &&Spinbox

>>> from tkinter import *
>>> from tkinter import ttk
>>> root=Tk()
>>> month=StringVar() #新建一个变量month，变量类型为StringVar
>>> combobox=ttk.Combobox(root,textvariable=month)  #新建一个combobox， 显示内容为 month
>>> combobox.pack() #排版
>>> combobox.config(values=("Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"))  #combobox可选内容如预约
 >>> month.get() #其实如果选了Jan 那么month的值就是Jan
''
>>> month.get()
'Mar'
>>> mont.set("adsf")
Traceback (most recent call last):
File "<pyshell#9>", line 1, in <module>
mont.set("adsf")
NameError: name 'mont' is not defined
>>> month.get()
'Marsf'
>>> year=StringVar()
>>> Spinbox(root,from _=1990,to=2017,textvariable=year).pack()   #只能上下切的Spinbox 自动生成日期是from—— 1990  到2017. 一个下拉框
SyntaxError: invalid syntax
>>> Spinbox(root,from _=1990,to=2017,textvariable=year).pack()
SyntaxError: invalid syntax
>>> Spinbox(root,from_=1990,to=2017,textvariable=year).pack()
>>> year.
SyntaxError: invalid syntax
>>> year.get()
'2017'
>>> year.set(1994)
>>> year.set(18840)
>>> year
<tkinter.StringVar object at 0x03FB4650>
>>>