Python把cmd输出实时保存到log文件

把python在cmd的打印实时保存到log文件

from ctypes import *
import sys

class Logger(object):
    def __init__(self, filename='default.log', stream=sys.stdout):
	    self.terminal = stream
	    self.log = open(filename, 'w')

    def write(self, message):
        self.terminal.write(message)
        self.terminal.flush()
        self.log.write(message)
        self.log.flush()

    def flush(self):
	    pass

sys.stdout = Logger("tmp.log", sys.stdout)
sys.stderr = Logger("tmp.log_file", sys.stderr)	

print("this is a test!")