解释这个代码：def get_movies(start): url = "https://movie.douban.com/top250?start=%d&filter=" % start lists = [] headers = { "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36"} html = requests.get(url,headers=headers) soup = BeautifulSoup(html.content, "html.parser") items = soup.find("ol", class_="grid_view").find_all("li") for i in items: movie = {} movie["rank"] = i.find("em").text movie["link"] = i.find("div","pic").find("a").get("href") movie["mdirecter"]=re.findall(re.compile(r'<p class="">(.*?)</p>',re.S),str(i))[0].replace("...<br/>","").replace("\n ","") movie["name"] = i.find("span", "title").text movie["score"] = i.find("span", "rating_num").text movie["quote"] = i.find("span", "inq").text if(i.find("span", "inq")) else "" lists.append(movie) return lists

这是一个用于从豆瓣电影top250中获取电影信息的Python函数。函数接受一个参数 start，用于指定从哪个电影开始获取信息。函数首先根据 start 构建请求url，然后使用 requests 库发送请求获取网页内容。接着使用 BeautifulSoup 库解析网页内容，从中提取出电影信息。

具体来说，函数会先从网页内容中找到 class 为“grid_view”的 ol 标签，然后遍历其中的每个 li 标签。对于每个 li 标签，函数会解析出电影的排名、链接、导演、名称、评分和简介，并将这些信息存储到一个字典中，最后将这个字典添加到一个列表中。最后，函数返回所有电影的信息列表。

相关问题

生成爬虫代码 用python 网址https://movie.douban.com/top250?start=0&filter= 爬取电影图片保存到文件夹 爬取电影名、导演、演员、评分、评分人数保存到txt文件

以下是生成爬虫代码的步骤：

1. 安装 requests、beautifulsoup4 和 os 库，可以使用 pip 工具进行安装。

2. 创建一个 Python 文件，命名为 "douban_spider.py"。

3. 导入 requests、beautifulsoup4 和 os 库：

import requests
from bs4 import BeautifulSoup
import os

4. 定义一个函数，用于爬取电影信息和图片，并保存到本地：

def spider(start):
    url = f'https://movie.douban.com/top250?start={start}&filter='
    response = requests.get(url)
    soup = BeautifulSoup(response.text, 'html.parser')
    items = soup.find_all('div', class_='item')
    for item in items:
        # 获取电影信息
        name = item.find('span', class_='title').text
        director = item.find('div', class_='bd').find_all('p')[0].text.split(':')[1].split('\n')[0].strip()
        actors = item.find('div', class_='bd').find_all('p')[0].text.split(':')[2].strip().split('\xa0\xa0\xa0')
        rating = item.find('span', class_='rating_num').text
        rating_num = item.find('div', class_='star').find_all('span')[3].text[:-3]
        # 保存电影信息到文本文件
        with open('movies.txt', 'a', encoding='utf-8') as f:
            f.write(f'电影名：{name}\n导演：{director}\n演员：{actors}\n评分：{rating}\n评分人数：{rating_num}\n\n')
        # 下载电影图片并保存到本地
        img_url = item.find('img')['src']
        img_response = requests.get(img_url)
        with open(os.path.join('movies', f'{name}.jpg'), 'wb') as f:
            f.write(img_response.content)

5. 创建一个名为 "movies" 的文件夹，用于保存电影图片。

if not os.path.exists('movies'):
    os.mkdir('movies')

6. 调用函数，爬取前 250 部电影的信息和图片，并保存到本地：

for i in range(0, 250, 25):
    spider(i)

以上就是生成爬虫代码的步骤，可以将上述代码保存到 "douban_spider.py" 文件中，并在命令行中运行该文件即可。

import requests from bs4 import BeautifulSoup import csv def get_top250_movies(): url = 'https://movie.douban.com/top250' headers = { 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3'} movie_info_list = [] for i in range(0, 250, 25): params = {'start': str(i)} res = requests.get(url, headers=headers, params=params) soup = BeautifulSoup(res.text, 'html.parser') movie_list = soup.find_all('div', class_='info') for movie in movie_list: title = movie.find('span', class_='title').text info = movie.find('div', class_='bd').p.text.strip().split('\n') director = info[0][4:] actors = info[1][3:] year = info[1][-5:-1] rating = movie.find('span', class_='rating_num').text comment_num = movie.find('div', class_='star').find_all('span')[3].text[:-3] movie_info_list.append([title, director, actors, year, rating, comment_num]) return movie_info_list def save_to_csv(movie_info_list): with open('movie_info.csv', 'w', newline='', encoding='utf-8-sig') as f: writer = csv.writer(f) writer.writerow(['电影名称', '导演', '演员', '上映年份', '评分', '评论数']) for movie_info in movie_info_list: writer.writerow(movie_info) if __name__ == '__main__': movie_info_list = get_top250_movies() save_to_csv(movie_info_list) print('电影信息保存成功！')将此代码运行成功后保存的六个信息分别单独成一列

可以在save_to_csv函数中将每个信息分别写入csv文件中的一列，修改后代码如下：

import requests
from bs4 import BeautifulSoup
import csv

def get_top250_movies():
    url = 'https://movie.douban.com/top250'
    headers = {
        'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3'
    }
    movie_info_list = []
    for i in range(0, 250, 25):
        params = {'start': str(i)}
        res = requests.get(url, headers=headers, params=params)
        soup = BeautifulSoup(res.text, 'html.parser')
        movie_list = soup.find_all('div', class_='info')
        for movie in movie_list:
            title = movie.find('span', class_='title').text
            info = movie.find('div', class_='bd').p.text.strip().split('\n')
            director = info[0][4:]
            actors = info[1][3:]
            year = info[1][-5:-1]
            rating = movie.find('span', class_='rating_num').text
            comment_num = movie.find('div', class_='star').find_all('span')[3].text[:-3]
            movie_info_list.append([title, director, actors, year, rating, comment_num])
    return movie_info_list


def save_to_csv(movie_info_list):
    with open('movie_info.csv', 'w', newline='', encoding='utf-8-sig') as f:
        writer = csv.writer(f)
        writer.writerow(['电影名称', '导演', '演员', '上映年份', '评分', '评论数'])
        for movie_info in movie_info_list:
            writer.writerow(movie_info)

    # 将每个信息分别写入csv文件中的一列
    with open('movie_info.csv', 'r', newline='', encoding='utf-8-sig') as f_read:
        with open('movie_info_new.csv', 'w', newline='', encoding='utf-8-sig') as f_write:
            reader = csv.reader(f_read)
            writer = csv.writer(f_write)
            for row in reader:
                for i in range(len(row)):
                    writer.writerow([row[i]])

    # 删除原文件
    import os
    os.remove('movie_info.csv')
    # 重命名新文件
    os.rename('movie_info_new.csv', 'movie_info.csv')


if __name__ == '__main__':
    movie_info_list = get_top250_movies()
    save_to_csv(movie_info_list)
    print('电影信息保存成功！')

运行修改后的代码，会在同级目录下生成一个名为'movie_info.csv'的文件，其中每个信息分别单独成一列。