public static void InsertEmployees(List <Employee> employees, PayrollContext context)
        {
            var departments = context.Departments.ToList();

            foreach (var employee in employees)
            {
                int id = departments.Where(d => d.Name == employee.Department).First().Id;
                employee.DepartmentId = id;
            }
            context.AddRange(employees);
            context.SaveChanges();
        }