无法从scrapy中提取图像链接

ITEM_PIPELINES = {
    'scrapy.pipelines.images.ImagesPipeline': 1
}

IMAGES_STORE = 'your_image_directory'

import scrapy

class MyItem(scrapy.Item):
    image_urls = scrapy.Field()
    images = scrapy.Field()

import scrapy
from myproject.items import MyItem

class MySpider(scrapy.Spider):
    name = 'myspider'
    start_urls = ['http://example.com']

    def parse(self, response):
        item = MyItem()
        item['image_urls'] = response.css('img::attr(src)').extract()
        yield item

from scrapy.pipelines.images import ImagesPipeline

class MyImagesPipeline(ImagesPipeline):
    def file_path(self, request, response=None, info=None):
        # 自定义保存路径的方式，可根据需求修改
        return 'full/{0}'.format(request.url.split('/')[-1])

    def thumb_path(self, request, thumb_id, response=None, info=None):
        # 自定义缩略图保存路径的方式，可根据需求修改
        return 'thumbs/{0}/{1}.jpg'.format(thumb_id, request.url.split('/')[-1])

    def item_completed(self, results, item, info):
        image_paths = [x['path'] for ok, x in results if ok]
        if not image_paths:
            raise DropItem('Image download failed')
        item['images'] = image_paths
        return item

ITEM_PIPELINES = {
    'myproject.pipelines.MyImagesPipeline': 1
}