How can this Perl regular expression be expressed in Python?

[Gabriel Genellina]

En Wed, 14 Feb 2007 04:11:37 -0300, John Nagle <nagle at animats.com>  
escribió:

> Gabriel Genellina wrote:
>> En Wed, 14 Feb 2007 01:07:33 -0300, John Nagle <nagle at animats.com>
>> escribió:
>>
>>> Here's a large Perl regular expression, from a Perl address parser in
>>> CPAN:
>>>
>>>     use re 'eval';
>>>      $Addr_Match{street} = qr/
>>>          (?:
>>>            # special case for addresses like 100 South Street
>>>            (?:($Addr_Match{direct})\W+           (?{ $_{street} = $^N  
>>> })
>>>               ($Addr_Match{type})\b              (?{ $_{type}   = $^N  
>>> }))

>     Incidentally, does anybody know what "$^N" means in Perl?  That
> abbreviation isn't in the list of special variables.

 From the context it appears to be the "last matched group", or something  
like that... but best look for some authoritative answer.

-- 
Gabriel Genellina