'Is it now past this problem\'s due date, including grace period?'

def is_past_due(self):

    due_date = self.due
    if ((self.graceperiod is not None) and due_date):
        close_date = (due_date + self.graceperiod)
    else:
        close_date = due_date
    return ((close_date is not None) and (datetime.datetime.now(UTC()) > close_date))
