'Finds `SubtitleListFile` corresponding to this entry, if it exists.'

@with_session
def _find_entry(self, entry, match_regexp=False, session=None):

    res = None
    if match_regexp:
        for regexp in self._db_list(session).regexps:
            if re.search(regexp.regexp, entry[u'title'], re.IGNORECASE):
                res = regexp
    else:
        res = self._db_list(session).regexps.filter((RegexListRegexp.regexp == entry.get(u'regexp', entry[u'title']))).first()
    return res
