请将刚才的代码进行优化，并添加注释，最后将背景图片换与永劫无间相关的

代码优化和注释如下：

import requests
from bs4 import BeautifulSoup
from PIL import Image

# 请求永劫无间相关图片的url
url = "https://www.baidu.com/s?wd=%E6%B0%B8%E5%8A%AB%E6%97%A0%E9%97%B4&tn=80035161_2_dg&ie=utf-8&ch=3&ssl_sample=normal&is_ss=1&srcqid=385902162837287142&rtt=1&bsst=1"

# 发送请求并获取响应
response = requests.get(url)

# 将响应的html页面转换成BeautifulSoup对象
soup = BeautifulSoup(response.content, "html.parser")

# 获取所有图片的标签
img_tags = soup.find_all("img")

# 遍历所有图片标签
for i, img in enumerate(img_tags):
    # 获取图片的url
    img_url = img.get("src")
    # 如果url以http开头，则发送请求，获取图片并保存
    if img_url.startswith("http"):
        response = requests.get(img_url)
        img_name = f"永劫无间{i}.jpg"
        with open(img_name, "wb") as f:
            f.write(response.content)
        # 打开图片并显示
        Image.open(img_name).show()

# 更改背景图片
from ctypes import windll, c_buffer

# 背景图片路径
img_path = "永劫无间0.jpg"

# 设置背景图片
SPI_SETDESKWALLPAPER = 20
windll.user32.SystemParametersInfoW(SPI_SETDESKWALLPAPER, 0, img_path, 3)

下面是更改后的背景图片，与永劫无间相关：