关于保存图片的问题

请老师指点为什么新闻详情页里有多张图片的时候，只能下载下来一张啊？

class DongqiudiImagePipeline(ImagesPipeline):
    def get_media_requests(self, item, info):
        for image_url in item['image_urls']:
            yield scrapy.Request(url=image_url, meta={"item": item})

    def item_completed(self, results, item, info):
        image_paths = []
        for ok, x in results:
            if ok:
                image_paths.append(x['path'])
        if not image_paths:
            raise DropItem('Item contains no images')

    def file_path(self, request, response=None, info=None):
        img_name = request.meta['item']['title']+'.jpg'
        return img_name
        
        
crawl_dongqiudi中获取image_urls的xpath
news_info['image_urls'] = response.xpath("//div[@class='con']/div/p/img/@data-src").extract()