public static void Operands()
        {
            var provider = new CommandLineOptionsProvider(new[] { new Operand("a") });

            provider.Load();

            provider
            .TryGet("", out var value)
            .Should()
            .BeTrue();

            value
            .Should()
            .Be("a");
        }
        public static void Values()
        {
            var provider = new CommandLineOptionsProvider(new[] { new OptionArgument("a", "1"), new OptionArgument("a", "2") });

            provider.Load();

            provider
            .TryGet("a:1", out var value)
            .Should()
            .BeTrue();

            value
            .Should()
            .Be("2");
        }