用Python帮我写一个简单的爬虫

下面是一个简单的Python爬虫示例，用于抓取网页中的所有图片链接。

```python
import requests 
from bs4 import BeautifulSoup

url = "http://example.com" 
r = requests.get(url)

soup = BeautifulSoup(r.content, 'html5lib') 
links = soup.find_all('img') 

for link in links: 
    image_url = link.get('src') 
    print(image_url)
```