'Returns the latest item\'s pubdate. If none of them have a pubdate,
this returns the current date/time.'

def latest_post_date(self):

    updates = [i[u'pubdate'] for i in self.items if (i[u'pubdate'] is not None)]
    if (len(updates) > 0):
        updates.sort()
        return updates[(-1)]
    else:
        return datetime.datetime.now()
