public async Task <List <DBUser> > GetCurrentBatchUsers()
        {
            var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);
            var batch  = await _userService.GetBatch(userId);

            if (batch == null)
            {
                return(null);
            }
            else
            {
                return(await _batchService.GetBatchStudents(batch.Id));
            }
        }