如何将两个IEnumerables合并(或压缩)？

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        List<int> list1 = new List<int> { 1, 2, 3 };
        List<int> list2 = new List<int> { 4, 5, 6 };

        IEnumerable<int> mergedList = list1.Concat(list2);

        foreach (int item in mergedList)
        {
            Console.WriteLine(item);
        }
    }
}

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