using System;

using System.Globalization;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var Iso3ToIso2Mapping = CultureInfo.GetCultures(CultureTypes.SpecificCultures)

          .Select(ci => new RegionInfo(ci.LCID))

          .GroupBy(ri => ri.ThreeLetterISORegionName)

          .ToDictionary(g => g.Key, g => g.First().TwoLetterISORegionName);

        var iso2CountryCode = Iso3ToIso2Mapping["BRA"];

        Console.WriteLine(iso2CountryCode);

    }

}