public void TestBuyItem()
{
_repo.BuyItem(new PurchaseHistory()
{
Id = "TID09",
ItemId = "I002",
BuyerId = "B001",
SellerId = "S001",
NumberOfItems = "1",
DateTime = DateTime.Now,
Remarks = "Nothing",
TransactionType = "Debit"
});
var result = _repo.GetPurchaseHistory("TID09");
Assert.IsNotNull(result);
}