public bool Update(Employee emp)
 {
     int index = lst.FindIndex(e => e.ID == emp.ID);
     lst.RemoveAt(index);
     lst.Add(emp);
     return true;
 }
 public bool Update(Employee emp)
 {
     return repo.Update(emp);
 }
 public bool Delete(Employee emp)
 {
     repo.Delete(emp);
     return true;
 }
 public bool Create(Employee emp)
 {
     repo.Create(emp);
     return true;
 }
 public bool Delete(Employee emp)
 {
     lst.Remove(emp);
     return true;
 }
 public bool Create(Employee emp)
 {
     lst.Add(emp);
     return true;
 }