python - 理解python中的正则表达式

Question

我正在用 python 学习 re。
我理解以下示例中的所有其他内容。
但是，我真的不明白以下示例中的特殊(在标签中)意味着什么。

re.compile('((?P<special>[0:-])\s)')

知道的请帮忙

Answer 1

它们被称为命名捕获组。

快速解释 here :

Python's regex module was the first to offer a solution: named capture. By assigning a name to a capturing group, you can easily reference it by name. (?P<name>group) captures the match of group into the backreference "name". You can reference the contents of the group with the numbered backreference \1 or the named backreference (?P=name).