import threading,time

print('第一线程（默认）：程序开始啦！')

def takeANap():

    time.sleep(5)

    print('第二线程：5秒到，我醒来啦！')

#创建并启动多线程

t=threading.Thread(target=takeANap)

t.start()

print('第一线程（默认）：程序结束啦！')

'''

输出：

第一线程（默认）：程序开始啦！

第一线程（默认）：程序结束啦！

>>> 第二线程：5秒到，我醒来啦！

'''

import threading

##多线程传递多参数print('Cats','Dogs','Frogs',sep='&')=>Cats & Dogs & Frogs：

threadObj = threading.Thread(target=print, args=['Cats', 'Dogs', 'Frogs'],kwargs={'sep': ' & '})

threadObj.start()

##输出：Cats & Dogs & Frogs

#! python3

# multidownloadXkcd.py - Downloads XKCD comics using multiple threads.

import requests, os, bs4, threading

os.makedirs('xkcd', exist_ok=True) # store comics in ./xkcd

def downloadXkcd(startComic, endComic):

    for urlNumber in range(startComic, endComic):

        # Download the page.

        print('Downloading page http://xkcd.com/%s...' % (urlNumber))

        res = requests.get('http://xkcd.com/%s' % (urlNumber))

        res.raise_for_status()

        soup = bs4.BeautifulSoup(res.text)

        # Find the URL of the comic image.

        comicElem = soup.select('#comic img')

        if comicElem == []:

            print('Could not find comic image.')

        else:

            comicUrl = comicElem[0].get('src')

            # Download the image.

            print('Downloading image %s...' % (comicUrl))

            res = requests.get(comicUrl)

            res.raise_for_status()

            # Save the image to ./xkcd

            imageFile = open(os.path.join('xkcd', os.path.basename(comicUrl)), 'wb')

            for chunk in res.iter_content(100000):

                imageFile.write(chunk)

            imageFile.close()

# Create and start the Thread objects.

downloadThreads = [] # a list of all the Thread objects

for i in range(0, 1400, 100): # loops 14 times, creates 14 threads

    downloadThread = threading.Thread(target=downloadXkcd, args=(i, i + 99))

    downloadThreads.append(downloadThread)

    downloadThread.start()

# Wait for all threads to end.

for downloadThread in downloadThreads:

    downloadThread.join()

print('Done.')