Python如何在类中定义装饰器

# _*_ encoding:utf-8 _*_
import logging
from time import localtime, time, strftime, sleep
from random import choice
 
 
class CallingInfo(object):
 
    # 通过name对为日志分组
    def __init__(self, name):
        log = logging.getLogger(name)
        # 设置log的输出级别
        log.setLevel(logging.INFO)
        # 输入到文件中
        fh = logging.FileHandler(name + '.log')
        log.addHandler(fh)
        log.info('start'.center(50, '-'))
        # 将log变成实例属性
        self.log = log
        # 定义日志的输出格式,函数名、开始时间，执行时间，调用次数
        self.formatter = '%(func)s -> [%(time)s - ' \
                         '%(used)s - %(n_calls)s]'
 
    # 定义装饰器函数
    def info(self, func):
        def wrapper(*args, **kwargs):
            wrapper.n_calls += 1
            lt = localtime()
            start = time()
            res = func(*args, **kwargs)
            used = time() - start
            info = dict()
            info['func'] = func.__name__
            info['time'] = strftime('%x %X', lt)
            info['used'] = used
            info['n_calls'] = wrapper.n_calls
            msg = self.formatter % info
            # 输出日志
            self.log.info(msg)
            return res
 
        # 统计函数调用次数，函数属性类似于函数内的静态变量
        wrapper.n_calls = 0
        return wrapper
 
    # 动态修改formatter参数
    def set_formatter(self, formatter):
        # 修改实例属性
        self.formatter = formatter
 
    # 动态的打开和关闭日志输出，设置level输出级别
    def turn_on(self):
        # INFO级别会输出日志
        self.log.setLevel(logging.INFO)
 
    def turn_off(self):
        # 抬高日志输出级别就会关闭
        self.log.setLevel(logging.WARN)
 
 
# 将f和g输出到一个日志当中，h输出到另一个,需要创建2个实例
# 创建类的实例，使用实例的info方法去装饰函数
c_info1 = CallingInfo('my_log1')
c_info2 = CallingInfo('my_log2')
# 将c_info1日志修改为如下格式
c_info1.set_formatter('%(func)s -> [%(time)s - %(n_calls)s]')
# 关闭c_info2的日志输出
c_info2.turn_off()
 
 
@c_info1.info
def f():
    print('in f')
 
 
@c_info1.info
def g():
    print('in g')
 
 
@c_info2.info
def h():
    print('in h')
 
 
# 测试代码, 循环50次
for _ in range(50):
    # 随机调用上面三个函数中的一个
    choice([f, g, h])()
    # 随机秒数的睡眠
    sleep(choice([0.5, 1, 1.5]))