Python Regex para una URL
import re
url = '<p>Hello World</p><a href="http://example.com">More Examples</a><a href="http://example2.com">Even More Examples</a>'
urls = re.findall('https?://(?:[-\w.]|(?:%[\da-fA-F]{2}))+', url)
>>> print urls
['http://example.com', 'http://example2.com']
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