数据库model自定义字段

class BIUser(db.Model):
    __tablename__ = 'bi_user'

    id = db.Column(db.BIGINT, primary_key=True)
    user_id = db.Column(db.BIGINT, unique=True, nullable=False, index=True)
    username = db.Column(db.String(255), index=True)
    og_account = db.Column(db.String(255), index=True)
    facebook_id = db.Column(db.String(255))
    email = db.Column(db.String(255), index=True)
    email_validate_time = db.Column(OGInsertableAwareDateTime, index=True)
    email_promotion_allowed = db.Column(db.Boolean)

    account_status = db.Column(db.String(255))






class OGInsertableAwareDateTime(types.TypeDecorator):
    impl = ArrowType

    # def process_bind_param(self, value, _):
    #     if value is not None:
    #         if isinstance(value, datetime):
    #             return arrow.get(value).replace(hours=-8).to(app.config['APP_TIMEZONE'])
    #         return arrow.get(value).replace(hours=-8).to(app.config['APP_TIMEZONE'])
    def process_bind_param(self, value, _):
        if value is not None:
            return arrow.get(value).replace(hours=-8)

    def process_result_value(self, value, _):
        if value is not None:
            return value.to(app.config['APP_TIMEZONE']