private void btnAddTrainee_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                bl.addTrainee(HodayaY);
            }

            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
        private void btnAddTrainee_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                bl.addTrainee(Abigail);
                MessageBox.Show("You have successfully added a trainee");
            }

            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }