using LiskovSubstitution.Interfaces; namespace LiskovSubstitution.Classes { public class User : IUser { public string ReadFromFile(string filename) { return filename; } public void DownloadFile(string filename) { Console.WriteLine("Downloaded the file."); } public void GetDataFromFile(string filename) { Console.WriteLine("Got data from the file."); } public void CheckFile(string filename) { Console.WriteLine("Checked the file."); } } }