regex for a href to add a target=“_blank”

也许有点像 pyquery ?

>>> from pyquery import PyQuery
>>> d = PyQuery('<a href="http://google.com">My Link</a>')
>>> print d('a').attr('target', '_blank')
<a href="http://google.com" target="_blank">My Link</a>

如果你不想用regexp做,你可以

>>> import re

>>> link = """<a href="somesite">This is the link to some site</a>"""

>>> e = re.sub(r'<a(?P<in_a>[^>]+)>(?P<in_link>[^<]+)</a>',
       r'<a \g<in_a> target="_blank" > \g<in_link> </a>',
       link,
       )
>>> print e
<a  href="somesite" target="_blank" > This is the link to some site </a>