Django __gt filter return the duplicate item
Django is storing time in database with more precision, than seconds. So if you time_at holds exact time of 12:45:44, query for database will retrieve fields that have time more than that just by miliseconds, so time of field retrieved from database can have 12:45:44.231 and it will be retrieved.
I want to fetch items from my model by using time_created as criteria.
If the latest item I fetched was posted at 12:45:44, I store it in request.session['time_at'] = 12:45:44 and use it to fetch item that are later than the last fetched. 
new_notice = Notify.objects.filter(time_created__gt = request.session['time_at']) 
This is supposed to return items with time from 12:45:45 but it still return the ones with 12:45:44 which is making me have duplicate of items I have already fetched. 
How do I deal with this the right way?