public void Handle(ChildCheckedOutDomainEvent domainEvent)
        {
            School school = schoolReadOnlyRepository.GetSchool(domainEvent.AggregateRootId).Result;

            if (school.Version != domainEvent.Version)
            {
                throw new TransactionConflictException(school, domainEvent);
            }

            school.Apply(domainEvent);
            schoolWriteOnlyRepository.UpdateSchool(school).Wait();
        }