如何在amazon爬行器中使用scrapy的Itemloader，以便从输出中删除所有换行符或额外的空格

from scrapy.loader import ItemLoader
from scrapy.loader.processors import TakeFirst, MapCompose, Join

class AmazonItemLoader(ItemLoader):
    default_output_processor = TakeFirst()

from scrapy import Spider
from myproject.items import AmazonItem

class AmazonSpider(Spider):
    name = 'amazon'
    start_urls = ['https://www.amazon.com']

    def parse(self, response):
        loader = AmazonItemLoader(item=AmazonItem(), response=response)
        loader.add_xpath('title', '//h1/text()')
        loader.add_xpath('price', '//span[@class="price"]/text()')
        loader.add_xpath('description', '//div[@class="description"]/text()')
        item = loader.load_item()
        return item