public Professor_exception_list(Class.Teacher teacher)
        {
            InitializeComponent();

            exceptionData = Module.GetExceptionListData(teacher);
            this.list_of_exceptions.DataContext = exceptionData;
        }
 public Course_students(int courseId, Class.Teacher teacher)
 {
     InitializeComponent();
     this.teacher  = teacher;
     this.cours_id = courseId;
     studentsData  = Module.GetStudentsMark(cours_id, teacher);
     this.course_student_list.DataContext = studentsData;
 }