public EditModel(Guid assessmentId, string assessmentName, decimal? totalMarks, IList<GradeBoundary> boundaries, GradeBoundary newBoundary)
 {
     AssessmentId = assessmentId;
     AssessmentName = assessmentName;
     TotalMarks = totalMarks;
     Boundaries = boundaries;
     NewBoundary = newBoundary;
 }