python文本处理

1.在文本提取URL

这个主要用于爬虫技术：

把爬取的html页面保存为一个字符串，再从字符串中进行提取URL

比如把一个字符串保存在文件中

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然后使用findall()函数进行查找和正则表达式有关的实例。
import re

with open("pathurl_example.txt") as file:
        for line in file:
            urls = re.findall('https?://(?:[-w.]|(?:%[da-fA-F]{2}))+', line)
            print(urls)