using NorthBridgeContract.DataModels; namespace NorthBridgeContract.BusinessLogicsContracts; public interface IBuyerBusinessLogicContract { List GetAllBuyers(); BuyerDataModel GetBuyerByData(string data); void InsertBuyer(BuyerDataModel buyerDataModel); void UpdateBuyer(BuyerDataModel buyerDataModel); void DeleteBuyer(string id); }