__file__ = open(r'log.txt', 'a')

print >>__file__, "hello, world!"

__file__.close()

__stdout__ = sys.stdout

sys.stdout = open(r'log.txt', 'a')

print "hello, world!"

sys.stdout.close()

sys.stdout = __stdout__

#-*- coding:utf8 -*-

import sys

class stdout:

    def __init__(self):

        self.buff = []

        self.__file__ = open(r'log.txt', 'a')

        self.__stdout__ = sys.stdout

    def write(self, s):

        self.buff.append(s)

        self.__file__.write(s)

        self.__file__.flush()

        self.__stdout__.write(s)

    def flush(self):

        self.buff = []

        self.__stdout__.flush()

    def close(self):

        self.__file__.close()

    def reset(self):

        sys.stdout = self.__stdout__

if __name__ == '__main__':

    sys.stdout = stdout()

    for i in xrange(10):

        print "hello, world!"

    sys.stdout.close()

    #sys.stdout.__file__.close()

    sys.stdout.reset()

    #sys.stdout = sys.stdout.__stdout__

    print "im back!"