How to use the ramp-engine.rampbkd.model.EventScoreType.query.filter_by function in ramp-engine

def official_score_type(self):
        return EventScoreType.query.filter_by(
            event=self, name=self.official_score_name).one()

def __init__(self, name, event_team, session):
        self.name = name
        self.event_team = event_team
        sha_hasher = hashlib.sha1()
        sha_hasher.update(self.event.name.encode('utf-8'))
        sha_hasher.update(self.team.name.encode('utf-8'))
        sha_hasher.update(self.name.encode('utf-8'))
        # We considered using the id, but then it will be given away in the
        # url which is maybe not a good idea.
        self.hash_ = '{}'.format(sha_hasher.hexdigest())
        self.submission_timestamp = datetime.datetime.utcnow()
        event_score_types = EventScoreType.query.filter_by(
            event=event_team.event)
        for event_score_type in event_score_types:
            submission_score = SubmissionScore(
                submission=self, event_score_type=event_score_type)
            session.add(submission_score)
        self.reset()