Python 模块的参数可以用字典么？哪位大神看看我的代码哪里有问题，报错信息也在的

需要实现的功能是：
三级菜单
1.从文本内读出选项
2.查询每一级的选项，并能对选项进行增/删/改功能
3.每一级可以退出程序或者返回上一层

思路

三个操作模块，分别是 增/删/改 功能
三个查询模块，分别对每一级别进行查询

报错信息：
Traceback (most recent call last):
File "E:/python/day8/three menu.py", line 79, in <module>
shen()
File "E:/python/day8/three menu.py", line 37, in shen
elif city == 'a':FileAppend(menu)
File "E:/python/day8/three menu.py", line 17, in FileAppend
ExChange()
File "E:/python/day8/three menu.py", line 47, in ExChange
FileWrite.write(menu)
TypeError: expected a string or other character buffer object

# -*- coding: UTF-8 -*-

#__filename:three menu

#__time:2018/5/13 22:04



import io

import os



FileRead = io.open('city','r',encoding='utf8')

FileWrite= open('city_backup','w+')

menu = eval(FileRead.read())



def FileAppend(MenuAppend):



    CityAppend = raw_input("请输入添加的城市",)

    MenuAppend['CityAppend']={}

    ExChange()



def FileDel(MenuDel):

    CityDel = raw_input("请输入你要删除的城市",)

    MenuDel.pop('CityDel')

    ExChange()



def FileChance(MenuChance):

    CityChance = raw_input("请输入被替换的城市",)

    if CityChance in MenuChance : CityChanced = raw_input("请输入替换的城市",)

    MenuChance['CityChanced'] = MenuChance['CityChance']

    MenuChance.pop('CityChance')

    ExChange()



def shen():

    for i in menu:print (i)

    city = raw_input('请输入你选择的省份',)

    if city == 'q': exit()

    elif city == 'd':FileDel(menu)

    elif city == 'c':FileChance(menu)

    elif city == 'a':FileAppend(menu)

    elif (city in menu) and (menu[city]!=0): shi(city)

    elif menu[city]==0 :

        print "该省下面没有市，请添加"

        FileAppend(menu[city])

    else:

        print '请输入正确的省份'

        shen()



def ExChange():

    FileWrite.write(menu)

    FileRead.close()

    FileWrite.close()

    os.remove('FileRead')

    os.renames('FileWrite','FileRead')



def shi(city):

    for i in menu[city]: print (i)

    city1 = raw_input('请输入你选择的市或退出程序(Q)或返回上一级菜单(B)').strip()

    if city1 == 'b':shen()

    elif city1 == 'q':exit()

    elif city1 == 'd':FileDel(menu[city])

    elif city1 == 'c':FileChance(menu[city])

    elif city1 == 'a':FileAppend(menu[city])

    elif (city1 in menu[city])and (menu[city][city1]!=0):xian(city,city1)

    elif menu[city][city1]==0 : FileAppend( menu[city][city1])

    else:

        '请输入正确的市'

        shi(city)



def xian(city,city1):

    for i in menu[city][city1]: print (i)

    city2 = raw_input('请选择退出(Q)或返回(B) ')

    if city2 == 'b': shi(city)

    elif city2 == 'q': exit()

    elif city2 == 'd':FileDel(menu[city][city1])

    elif city2 == 'c':FileChance(menu[city][city1])

    elif city2 == 'a':FileAppend(menu[city][city1])

    else:

        '请输入正确的区或县'

        xian(city, city1)



shen()