public static Sales CreateSales(int id, DateTime dateTime, string fullName = "Test name", List <Worker> workers = null, ChiefWorker chief = null)
        {
            var sales = new Sales
            {
                Id             = id,
                EmploymentDate = dateTime,
                FullName       = fullName + id
            };

            if (chief != null)
            {
                sales.SetChief(chief);
            }

            if (workers != null)
            {
                foreach (var worker in workers)
                {
                    sales.AddSubordinates(worker);
                }
            }

            return(sales);
        }