public async Task <IActionResult> Index()
        {
            var userId    = int.Parse(_userManager.GetUserId(User));
            var isStudent = User.Claims.Any(u => u.Value == ClaimTypes.Student.ToString());

            return(View(await _assignmentService.GetAssignmentsGridInfo(userId,
                                                                        isStudent ? ClaimTypes.Student : ClaimTypes.Teacher)));
        }