twisted　reactor运行后，添加了addBoth函数，但是还是无法停止

	from scrapy.selector import Selector

	

	def get_response_callback(content):

		txt = str(content,encoding='utf-8')

		resp = Selector(text=txt)

		title = resp.xpath('//title/text()').extract_first()

		print(title)

	

	@defer.inlineCallbacks

	def task():

		url = 'http://www.baidu.com'

		d=getPage(url.encode('utf-8'))

		d.addCallback(get_response_callback)

		yield d



	def done():

		reactor.stop()



	def done1(*args,**kwargs):

		reactor.stop()



	task_list = 

	for i in range(4):

		d=task()

		task_list.append(d)



	dd = defer.DeferredList(task_list)



	dd.addBoth(done)



	reactor.run()