private void CreateInstance(CustomerRegisterCLI CLI)
        {
            CustomerRegisterCLI cli = CLI;

            string usersInput;

            while (true)
            {
                Console.WriteLine("Please enter a command:");
                usersInput = Console.ReadLine();
                cli.ValidateUsersInput(usersInput); // validates if input is a command name
                if (cli.InputIsValid)               // property to check input
                {
                    cli.CallCommand();              // call command if input is golden
                }
                else
                {
                    Console.WriteLine("Sorry, that is not a command.");
                }
            }
        }
 public CustomerRegister()
 {
     _cli = new CustomerRegisterCLI();
     CreateInstance(_cli);
 }