资料内容：
步骤1：定义数据结构（items.py）
import scrapy
class GlobalProductItem(scrapy.Item):
# 基础信息
name = scrapy.Field()
sku = scrapy.Field()
price = scrapy.Field()
currency = scrapy.Field()
source_site = scrapy.Field()
# 时间戳
crawl_time = scrapy.Field()
# 处理后字段
normalized_price = scrapy.Field(
serializer=lambda x: f"${x:.2f}" # 序列化处理
)
# 位置信息
ship_from_country = scrapy.Field()
ship_to_countries = scrapy.Field()
# 分类维度
category = scrapy.Field()
subcategory = scrapy.Field()
# 标记字段
discount_tag = scrapy.Field()
is_out_of_stock = scrapy.Field()
# 详情⻚元数据
product_url = scrapy.Field()
image_urls = scrapy.Field()
