static void FillLib(Library lib)
        {
            var readers = new[]
            {
                lib.RegReader("r1"),
                lib.RegReader("r2"),
                lib.RegReader("r3"),
            };

            var items = new LibItem[]
            {
                lib.AddBook("bb01", "50 Shades Of Grey", "E. L. James"),
                lib.AddBook("bb02", "Harry Potter And Some Thing", "J. K. Rolling"),
                lib.AddMagazine("m001", "Cosmopolitan", "Jan, 2015"),
                lib.AddMagazine("m002", "Занимательная механика", "Янв, 2015"),
            };

            lib.TakeItem(readers[0], items[0]);
            lib.TakeItem(readers[0], items[2]);

            lib.TakeItem(readers[1], items[0]);
            lib.TakeItem(readers[1], items[1]);
            lib.TakeItem(readers[1], items[2]);
            lib.TakeItem(readers[1], items[3]);
        }
 public void ReturnItem(Reader reader, LibItem item)
 {
     GetReadingItems(reader).Remove(item);
 }
 public void TakeItem(Reader reader, LibItem item)
 {
     GetReadingItems(reader).Add(item);
 }