static void Main(string[] args)
{
Customer customer1 = new Customer();
customer1.Id = 1;
customer1.CustomerName = "İrem";
customer1.CustomerSurname = "Deniz";
customer1.Job = "Graphic Designer";
customer1.PhoneNumber = 05351231212;
Customer customer2 = new Customer();
customer2.Id = 2;
customer2.CustomerName = "Tuna";
customer2.CustomerSurname = "Deniz";
customer2.Job = "Pilot";
customer2.PhoneNumber = 05353211212;
Customer customer3 = new Customer();
customer3.Id = 3;
customer3.CustomerName = "Zeynep";
customer3.CustomerSurname = "Deniz";
customer3.Job = "English Teacher";
customer3.PhoneNumber = 05352131212;
CustomerManager customerManager = new CustomerManager();
customerManager.AddingCustomer(customer1);
customerManager.DeletingCustomer(customer2);
customerManager.ListingCustomer(customer3);
}