public static IFdbDatabaseScopeProvider <FdbDirectorySubspace> CreateDirectoryScope([NotNull] this IFdbDatabaseScopeProvider provider, FdbDirectoryPath path)
 {
     return(provider.CreateScope <FdbDirectorySubspace>(async(db, cancel) =>
     {
         var folder = await db.Directory.CreateOrOpenAsync(path, cancel);
         return (db, folder);
     }));
 }