python-4-之with和open对比

open和file方法类似

打开文件使用后，要确保关闭，才是安全的：

#open your file heretry:    #write data to your filefinally:    file.close()

try:    f=open('test.txt','r')except:    passelse:    babababbabafinally:    f.close()

相比之下，with语句简洁许多，而且自带关闭

with open("somefile.txt") as somefile:do_something(somefile)

with open('abc.txt','r') as f:   print 'babababa'