#coding=utf-8import sysimport timef = open("demo.txt") #打开文件，python3中可以加参数encoding = "utf-8"#print (f.read())#文件光标会跳到最后#f.write("我今天学习了吗")    #w表示写，r表示读，a表示追加,r+ 读写，w+写读，a+追加读，rb二进制文件读（网络传输）#wb二进制写"""for i in range(5):     print (f.readline())for index,line in enumerate(f.readlines()):#下标和列表项，只适合读小文件    print index,line"""#另一种文件迭代器num = 0for line in f:    if num == 9:        continue    print line    num +=1print (f.tell())   #打印当前的指针位置print (f.seek(0))   #移动光标print (f.tell())print (f.name)print (f.flush())  #把书写的内容刷到硬盘上，适合实时写入文件for i in range(50):    time.sleep(0.1)    sys.stdout.write("#")   #CMD界面简易的进度表    sys.stdout.flush()f.truncate(10)#从当前光标往后截断留下前面的f.close()#文件的修改#coding=utf-8f = open("demo.txt","r")with open("demo.txt","r") as f:    print f.read()with open(file1) as obj1, open(file2) as obj2:"""f_new= open("demonew.txt","w")for line in f:    if "你的光照" in line:        line = line.replace("你的光照","abc")    f_new.write(line)f_new.close()print open("demonew.txt","r").read()"""