python根据搜索词下载百度图片

# coding=utf-8
"""根据搜索词下载百度图片"""
import re
import urllib

import os

def get_onepage_urls(onepageurl):
    """获取单个翻页的所有图片的urls+当前翻页的下一翻页的url"""
    try:
        page = urllib.urlopen(onepageurl)  # urllib.urlopen()方法用于打开一个URL地址
        html = page.read()  # read()方法用于读取URL上的数据
    except Exception as e:
        pic_urls = []
        fanye_url = ''
        return pic_urls, fanye_url
    pic_urls = re.findall('"objURL":"(.*?)",', html, re.S)
    fanye_urls = re.findall(re.compile(r'<a href="(.*)" class="n">下一页</a>'), html, flags=0)
    fanye_url = 'http://image.baidu.com' + fanye_urls[0] if fanye_urls else ''
    return pic_urls, fanye_url

Dir = os.path.join('E://', 'pic')

def down_pic(pic_urls):
    if not os.path.exists(Dir):
        os.makedirs(Dir)
    """给出图片链接列表, 下载所有图片"""
    for i, pic_url in enumerate(pic_urls):
        try:
            urllib.urlretrieve(pic_url, os.path.join(Dir, '%s.jpg') % str(i + 1))
            print('成功下载第%s张图片: %s' % (str(i + 1), str(pic_url)))
        except Exception as e:
            print('下载第%s张图片时失败: %s' % (str(i + 1), str(pic_url)))
            print(e)
            continue

if __name__ == '__main__':
    keyword = '狗狗'  # 关键词, 改为你想输入的词即可, 相当于在百度图片里搜索一样
    url_init_first = r'http://image.baidu.com/search/flip?tn=baiduimage&ipn=r&ct=201326592&cl=2&lm=-1&st=-1&fm=result&fr=&sf=1&fmq=1497491098685_R&pv=&ic=0&nc=1&z=&se=1&showtab=0&fb=0&width=&height=&face=0&istype=2&ie=utf-8&ctd=1497491098685%5E00_1519X735&word='
    url_init = url_init_first + urllib.quote(keyword, safe='/')
    all_pic_urls = []
    onepage_urls, fanye_url = get_onepage_urls(url_init)
    all_pic_urls.extend(onepage_urls)
    fanye_count = 0  # 累计翻页数
    while 1:
        onepage_urls, fanye_url = get_onepage_urls(fanye_url)
        fanye_count += 1
        print('第%s页' % fanye_count)
        all_pic_urls.extend(onepage_urls)
        if fanye_url == '' and onepage_urls == []:
            print('已到最后一页, 开始下载图片：')
            break
    down_pic(all_pic_urls)
    print '图片下载完毕'