def _build_days(self, data):
        "Get or Create Days based on schedule type and set of Days"
        created_days = []
        days = set([x[self.DATE_KEY] for x in data])
        for day in days:
            try:
                date = datetime.strptime(day, "%m/%d/%Y")
            except ValueError:
                [x.delete() for x in created_days]
                return messages.ERROR, u'Malformed data found: %s.' % day
            day, created = Day.objects.get_or_create(
                schedule=self.schedule, date=date
            )
            if created:
                created_days.append(day)
        return created_days
dataset/ETHPy150Open pinax/symposion/symposion/schedule/forms.py/ScheduleSectionForm._build_days/original