public Lesson geLessonByDayAndHour(string day, int hour) { Lesson l = SettingDatabase.GetLessonPractisePractitionerByDayAndHour(this, day, hour); if (l == null) { return(SettingDatabase.GetLessonLabPractitionerByDayAndHour(this, day, hour)); } else { return(l); } }