如何将脚本输出写入文件和命令行?

python -u MyLongRunngingScript.py | tee log.txt

class OutputSplitter(object):
    def __init__(self, real_output, *open_files):
        self.__stdout = real_output
        self.__fds = open_files
        self.encoding = real_output.encoding
    def write(self, string):
        self.__stdout.write(string) # don't catch exception on that one.
        self.__stdout.flush()
        for fd in self.__fds:
            try:
                fd.write(string)
                fd.flush()
            except IOError:
                pass # do what you want here. 
    def flush(self):
        pass # already flushed

stdout_saved = sys.stdout
logfile = open("log.txt","a") # check exception on that one.
sys.stdout = OutputSplitter(stdout_saved, logfile)

print

sys.stdout.flush() tee stdout