了解python中的正则表达式

Question

I am learning re in python.
I understand all other things in the following example.
but, i really dont understand what special (in tags) means in the following example.

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

kindly help if know it.

Answer 1

They're called named capturing groups.

A quick explanation 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).

Answer 2

这称为命名捕获组 。