实例文件操作

#把一个数字的list从小到大排序，然后写入文件，然后从文件中读取出来文件内容，然后反序，在追加到文件的下一行中


#!/usr/bin/env python
# -*- coding:utf-8 -*-
# @time: 2017/10/30 19:45
# Author: caicai
# @File: sample01.py
#import codecs
import ast
def listSort(a):
    b = sorted(a)
    return b

def listReverse(file):
    a1 = file
    print(a1)
    for a2 in a1:
        a2 = list(ast.literal_eval(a2))
        a2.reverse()
        return a2


def fileWrite(sort_list):
    f = open(‘2.txt‘,‘a‘)
    f.writelines(str(sort_list))
    f.writelines(‘\n‘)

    f.close()
    return

def fileRead():
    fd = open(‘2.txt‘)
    a2 = fd.readlines()
    fd.close()
    return a2

if __name__ == ‘__main__‘:
    list1 = [2,32,43,453,54,6,576,5,7,6,8,78,7,89 ]
    list1_sort = listSort(list1)
    fileWrite(list1_sort)
    file_read = fileRead()
    file_read2 = listReverse(file_read)
    fileWrite(file_read2)
    print(fileRead())

输出结果：
[‘[2, 5, 6, 6, 7, 7, 8, 32, 43, 54, 78, 89, 453, 576]\n‘, ‘[576, 453, 89, 78, 54, 43, 32, 8, 7, 7, 6, 6, 5, 2]\n‘]