public static void Benchmark()
        {
            var count = PackageProcessor.GetPackageInfos2(Packages, PackageCategories);

            if (count == 0)
            {
                throw new Exception();
            }
        }
        public static void Test()
        {
            // Warmup.
            for (int i = 0; i < 2; i++)
            {
                var count = PackageProcessor.GetPackageInfos(Packages, PackageCategories).Count();
                if (count == 0)
                {
                    throw new Exception();
                }
            }

            // Test.
            var stats = PackageProcessor.GetPackageInfos(Packages, PackageCategories)
                        .OrderByDescending(x => x.Item1)
                        .Take(15);

            foreach (var stat in stats)
            {
                Console.WriteLine($"{stat.Item1}    : {stat.Item2} ({stat.Item3})");
            }
        }