using System;
 
public class Test
{
	public static void Main()
	{
		Console.WriteLine(5.IsDynamicNull());
		Console.WriteLine(new DynamicNull().IsDynamicNull());
		Console.WriteLine(((object)null).IsDynamicNull());
 
		try
		{
			dynamic d = 5;
			Console.WriteLine(Extension.IsDynamicNull(d));
			Console.WriteLine("And now the fail");
			d.IsDynamicNull();
		// your code goes here
		}
		catch (Exception ex)
		{
			Console.WriteLine(ex);
		}
	}
}
 
public class DynamicNull
{
 
}
 
public static class Extension
{
	public static bool IsDynamicNull(this object objParam)
	{
	    dynamic obj = objParam;
	    return (obj == null || obj is DynamicNull);
	}
}

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