using System;

using System.Collections.Generic;

using System.Diagnostics;

public class Program

{

    public static void Main()

    {

        var dict = new Dictionary<string, string>();

        string invalidKey = "invalidKey";

        Debug.Assert((!dict.ContainsKey(invalidKey)), $"{nameof(dict)} contains the key {dict[invalidKey]}!");

        Console.WriteLine("Done");

    }

}