python scrapy basic

scrapy startproject todo
scrapy genspider -t basic todolist 192.168.126.181
cd todo
vi items.py
import scrapy

class TodoItem(scrapy.Item):
todo=scrapy.Field()
riqi=scrapy.Field()

vi todolist.py

-- coding: utf-8 --

import scrapy
from todo.items import TodoItem

class TodolistSpider(scrapy.Spider):
name = 'todolist'
allowed_domains = ['192.168.126.181']
start_urls = ['http://192.168.126.181:9999/simpletodo']

def parse(self, response):
    items=[]
    trs=response.xpath('//table//tr')
    for tr in trs:
      todos=tr.xpath('.//td[@class="todo"]')
      if len(todos)>0:
         item=TodoItem()
         item["todo"]=todos[0].xpath("./text()").extract()[0]
         item["riqi"]=todos[1].xpath("./text()").extract()[0]
         items.append(item)
    return items

scrapy crawl todolist