###爬虫框架scrapy练习
创建scrapy工程
scrapy startproject jianshu
工程目录： jianshu/ scrapy.cfg jianshu/ init.py items.py pipelines.py settings.py spiders/ init.py ...
运行scrapy爬虫
scrapy crawl yourspidername
可直接运行工程main.py文件
cmdline.execute("scrapy crawl jianshu".split())