full code for this assignment assignment - Abstract classes, Event Driven Applications and exception Handling.

Expected Output A local travel agency, Traveless, has hired your company to implement a new flight reservation management system to improve its productivity and services. After meeting with the agency, you realize that to tackle this complex request, you must break down the solution to three major parts: - Front-end GUI - Backend - Functional front end connected to the backend. Equipment and Materials For this assignment, you will need: - Visual Studio IDE - Supplied data files: flights.csv airports.csv airlines.csv