下载示例代码:

from bs4 import BeautifulSoup
from urllib.request import urlretrieve   #下载使用这个库
import requests
import os
import time

if __name__ == '__main__':
    list_url = []
    for num in range(1, 2):
        if num == 1:
            url = 'http://www.shuaia.net/index.html'
        else:
            url = 'http://www.shuaia.net/index_%d.html' % num
        headers = {
            "User-Agent": "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36"
        }
        req = requests.get(url=url, headers=headers)
        req.encoding = 'utf-8'
        html = req.text
        bf = BeautifulSoup(html, 'lxml')
        print(bf)
        targets_url = bf.find_all(class_='item-img')
        print('----------------------')
        print(targets_url)

        for each in targets_url:
            print('1111111')
            print(each)
            list_url.append(each.img.get('alt') + '=' + each.get('href'))

    print('连接采集完成')

    for each_img in list_url:
        img_info = each_img.split('=')   # 列表元素被等号分割成2个列表元素
        target_url = img_info[1]
        filename = img_info[0] + '.jpg'
        print('下载：' + filename)
        headers = {
            "User-Agent": "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36"
        }
        img_req = requests.get(url=target_url, headers=headers)
        img_req.encoding = 'utf-8'
        img_html = img_req.text
        img_bf_1 = BeautifulSoup(img_html, 'lxml')
        img_url = img_bf_1.find_all('div', class_='wr-single-content-list')
        img_bf_2 = BeautifulSoup(str(img_url), 'lxml')
        img_url = 'http://www.shuaia.net' + img_bf_2.div.img.get('src')
        if 'images' not in os.listdir():
            os.makedirs('images')
        urlretrieve(url=img_url, filename='images/' + filename)#下载(网址,命名)
        time.sleep(1)

    print('下载完成！')

显示下载进度

import os
import urllib

def cbk(a,b,c):  #这里定义的cbk用于显示下载进度
    '''回调函数
    @a:已经下载的数据块
    @b:数据块的大小
    @c:远程文件的大小
    '''
    per=100.0*a*b/c
    if per>100:
        per=100
    print '%.2f%%' % per

url='http://www.python.org/ftp/python/2.7.5/Python-2.7.5.tar.bz2'
dir=os.path.abspath('.')
work_path=os.path.join(dir,'Python-2.7.5.tar.bz2')
urllib.urlretrieve(url,work_path,cbk) #这里调用的cbk用于显示下载进度