Python小函数

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返回斐波那契数列列表

def fibs(num):    result = [0,1]    for i in range(num-2):        result.append(result[-2] + result[-1])    return result

获取文件尾缀

#extension.py def get_ext(frame):    dot = fname.rfind('.')    if dot == -1:        return ''    else:        return fname[dot + 1:]

将字符串插入到文件开头

def insert_title(title,fname = 'story.txt '):    f = open(fname , 'r+')    temp=f.read()    temp = title + '\n\n' + temp    f.seek(0) #让文件指针指向文件开头    f.write(temp)

写入文件

import osdef make_story():    if os.path.isfile('story.txt'):        print('story.txt already exists')    else:        f = open('story.txt', 'w')        f.write('写入的内容。。。\n')

附加到文本文件末尾

def add_to_story(line,fname = 'story.txt')    f = open(fname, 'a')#附加模式'a'    f.write(line)

使用pickle读取二进制

import pickledef make_pickled_file():    grades = {'alan' : [4,8,10,10],              'jack' : [2,1,4,5],              'james': [2,12,23,1],              'dick' : [12,None,99,1,1]}    outfile = open('grade.dat','wb')    pickle.dump(grades,outfile)#pickle.dump()将数据结构储存到磁盘def get_pickled_data():    infile = open('grade.dat','rb')    grades = pickle.load(infile)#pickle.load()从磁盘获取数据结构    return print(grades)

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