private static async Task AddSyndicationItemEntry(AtomEntry <SyndicationItem <PostalInfo> > entry, SyndicationContext context, CancellationToken ct)
        {
            var latestItem = await context
                             .PostalInfoLatestItems
                             .FindAsync(entry.Content.Object.PostalCode);

            if (latestItem == null)
            {
                latestItem = new PostalInfoLatestItem
                {
                    PostalCode = entry.Content.Object.PostalCode,
                    Version    = entry.Content.Object.Identificator?.Versie,
                    Position   = long.Parse(entry.FeedEntry.Id),
                    NisCode    = entry.Content.Object.MunicipalityNisCode,
                };

                UpdateNames(latestItem, entry.Content.Object.PostalNames);

                await context
                .PostalInfoLatestItems
                .AddAsync(latestItem, ct);
            }
            else
            {
                await context.Entry(latestItem).Collection(x => x.PostalNames).LoadAsync(ct);

                latestItem.Version  = entry.Content.Object.Identificator?.Versie;
                latestItem.Position = long.Parse(entry.FeedEntry.Id);
                latestItem.NisCode  = entry.Content.Object.MunicipalityNisCode;

                UpdateNames(latestItem, entry.Content.Object.PostalNames);
            }
        }
        private static void UpdateNames(PostalInfoLatestItem latestItem, IEnumerable <Postnaam> postalNames)
        {
            latestItem.PostalNames.Clear();

            foreach (var postalName in postalNames)
            {
                latestItem.PostalNames.Add(new PostalInfoPostalName
                {
                    Language   = postalName.GeografischeNaam.Taal,
                    PostalCode = latestItem.PostalCode,
                    PostalName = postalName.GeografischeNaam.Spelling
                });
            }
        }