Extract authors from byline string

byline_re

import re
def _extract_authors(byline):
        """
Takes one of our bylines returned from the Oxygen API, and
tries to split it out into individual authors. Only works up
to a triple byline.
"""
        fallback_byline = re.compile("([\-\w.&; ]+)")
        single_byline = re.compile("By ([\-\w.&; ]+)")
        double_byline = re.compile("By ([\-\w.&; ]+) and ([\-\w.&; ]+)")
        triple_byline = re.compile("By ([\-\w.&; ]+), ([\-\w.&; ]+) and ([\-\w.&; ]+)")
        byline_res = (
            triple_byline,
            double_byline,
            single_byline,
            fallback_byline
        )
        # Scan through from more complex to less complex. Take
        # first match, because single_byline will match the first
        # name from both double and triples.
        for regex in byline_res:
            matches = regex.search(byline)
            if matches:
                return matches.groups()
        # If not matches, return full byline
        return (byline,)