private async Task <Validation <Error, Department> > Validate(CreateDepartment create) =>
 (ValidateDepartmentName(create), ValidateBudget(create),
 public Task <Either <Error, int> > Handle(CreateDepartment request, CancellationToken cancellationToken) =>
 Validate(request)
 .MapT(PersistDepartment)
 .Bind(v => v.ToEitherAsync());