Python实现监控程序执行时间并将其写入日志的方法

# /usr/bin/python# -*- coding:utf-8 -*-from time import timedef logged(when):  def log(f,*args,**kargs):    print '''         called:          functions:%s          args: %r          kargs: %r    '''  % (f,args,kargs)  def pre_logged(f):    def wrapper(*args,**kargs):      log(f,*args,**kargs)      return f(*args,**kargs)    return wrapper  def post_logged(f):    def wrapper(*args,**kargs):      now = time()      try:        return f(*args,**kargs)      finally:        log(f,*args,**kargs)        print "time delta:%s" % (time()-now)    return wrapper  try:    return {"pre":pre_logged,"post":post_logged}[when]  except KeyError,e:    raise ValueError(e),'must be "pre" or "post"'@logged("post")def hello(name):  print "hello,",namehello("world!")'''等同于： hello = logged("post")(hello("world!"))'''