def METHOD_NAME(self, sample_email_template, sample_job):
    assert Notification.query.count() == 0
    data_1 = _notification_json(sample_email_template, job_id=sample_job.id, status="delivered")
    data_2 = _notification_json(sample_email_template, job_id=sample_job.id, status="created")
    notification_1 = Notification(**data_1)
    notification_2 = Notification(**data_2)
    dao_create_notification(notification_1)
    dao_create_notification(notification_2)
    assert Notification.query.count() == 2
    result = total_hard_bounces_grouped_by_hour(sample_email_template.service_id, datetime.utcnow() + timedelta(minutes=1))
    assert result == []