public Rent(IItem item, DateTime rentDate, DateTime deadLine)
        {
            this.Item = item;
            this.RentDate = rentDate;
            this.DeadLine = deadLine;
        }

        public Rent(IItem item, DateTime rentDate)
            : this(item, rentDate, rentDate.AddDays(30))
        {

        }

        public Rent(IItem item)
            : this(item, DateTime.Now, DateTime.Now.AddDays(30))
        {

        }

        public string RentFine { get; set; }