Python 刚学, 纠结于多线程 concurrent.futures 的错乱的问题,请教下各位?

按照手册实例结合自己想写的一个多访问的脚本,有了以下的代码.有 2 种写法的: 第 1 种速度快很多,但是出现多个 print 输出,实在想不出怎么冒出来的.是线程出错还是线程多余的.我开的 5 个线程,print(future_to_url) 对象也是 5 个.但是跑起来就多了出 3 个,而且文字还错乱了.

第 2 种暂时没有发现问题,求指教第一种为何会出现这种问题?

URLS = {'baidu':'http://www.baidu.com',
        'sogou':'http://www.sogou.com',
        'so':'http://www.so.com',
        'youku':'http://www.youku.com',
        'qq':'http://www.qq.com'
}

def load_url(s,args):
    weburl = args['url']
    if args['mark'] == 'baidu':
        print(s + "百度访问:" + weburl)
        rs = requests.get(weburl)
    if args['mark'] == 'so':
        print(s + "so:" + weburl)
        rs = requests.get(weburl)
    if args['mark'] == 'sogou':
        print(s + "搜狗访问:" + weburl)
        rs = requests.get(weburl)
    if args['mark'] == 'qq':
        print(s + "腾讯访问:" + weburl)
        rs = requests.get(weburl)
    if args['mark'] == 'youku':
        print(s + "优酷访问:" + weburl)
        rs = requests.get(weburl)
    return str(rs.status_code)
title = '速度与激情'
conData ={'year':'2015','actor':'范·迪塞尔,保罗·沃克,杰森·斯坦森,米歇尔·罗德里格兹','subname':'狂野时速 7'}
aa = []
start = datetime.datetime.now()
with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:

    # --------------------------------第 1 种.写法----------------------------------------------#
    future_to_url = {executor.submit(load_url,title,conData): (conData['mark'] ,conData['url']) for conData['mark'],conData['url'] in URLS.items()}
    print(future_to_url)
    for future in concurrent.futures.as_completed(future_to_url):
        url = future_to_url[future] #调用对应的 URL
        try:
            data = future.result() #获得函数返回的值
        except Exception as exc:
            print('%r generated an exception: %s' % (conData['url'], exc))#调试异常错误
        else:
            aa.append(data)

    #--------------------------------第 2 种.写法----------------------------------------------#
    # for conData['mark'],conData['url'] in URLS.items():
    #     future = executor.submit(load_url, title, conData)
    #     print(future)
    #     try:
    #         data = future.result() #获得函数返回的值
    #     except Exception as exc:
    #         print('%r generated an exception: %s' % (conData['url'], exc))#调试异常错误
    #     else:
    #         aa.append(data)

    executor.shutdown(wait=True)
end = datetime.datetime.now()
print (end-start)