如何使用结合regex & string/file操作和模式的存储实例的Python在文本文件中搜索模式?

So essentially I'm looking for specifically a 4 digit code within two angle brackets within a text file. I know that I need to open the text file and then parse line by line, but I am not sure the best way to go about structuring my code after checking "for line in file". So essentially I'm looking for specifically a 4