在scrapy中动态创建管道是可能的吗？

from scrapy import signals

class DynamicPipelineMiddleware(object):
    @classmethod
    def from_crawler(cls, crawler):
        middleware = cls()
        crawler.signals.connect(middleware.spider_opened, signal=signals.spider_opened)
        return middleware

    def spider_opened(self, spider):
        # 在爬虫启动时动态创建管道
        pipeline = MyDynamicPipeline()
        spider.pipelines[pipeline.name] = pipeline

    def process_spider_output(self, response, result, spider):
        # 在数据传递给管道之前进行处理
        for item in result:
            # 对数据进行处理
            processed_item = self.process_item(item)
            # 将处理后的数据传递给管道
            yield processed_item

    def process_item(self, item):
        # 对数据进行清洗、验证等操作
        return item

class MyDynamicPipeline(object):
    def __init__(self):
        self.name = 'my_dynamic_pipeline'

    def process_item(self, item, spider):
        # 处理数据的逻辑
        return item