using System;
using System.Collections.Generic;
 
public class Test
{
	public static void Main()
	{
		var stringList = new List<string> { "1", "2" };
		stringList.Shuffle();
		foreach (var l in stringList) Console.WriteLine(l);
 
		var intList = new List<int> { 1, 2 };
		intList.Shuffle();
		foreach (var l in intList) Console.WriteLine(l);
	}
}
 
public static class ListExtensions
{
	public static void Shuffle<T>(this List<T> list)
	{
		Console.WriteLine(typeof(T));
		var t = list[0];
		list[0] = list[1];
		list[1] = t;
	}
}

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