public bool RegisterNewBook(Book newBook, Copy copyOfNewBook, int QtyOfCopies)
 {
     if(InsertNewBook(newBook))
     {
         for (int a = 0; a < QtyOfCopies; a++)
             if (!InsertNewCopy(copyOfNewBook))
                 return false;
         return true;
     }
     return false;
 }
 public bool InsertNewBook(Book newBook)
 {
     return true;
 }
 public Copy[] GetAllCopies(Book book)
 {
     return new Copy[0];
 }