'Get a 3-item sequence representing the date consisting of a
year, month, and day number. Each number is either an integer or
None.'

def _get_date_tuple(self, mediafile):

    datestring = super(DateField, self).__get__(mediafile, None)
    if isinstance(datestring, six.string_types):
        datestring = re.sub('[Tt    ].*$', '', six.text_type(datestring))
        items = re.split('[-/]', six.text_type(datestring))
    else:
        items = []
    items = items[:3]
    if (len(items) < 3):
        items += ([None] * (3 - len(items)))
    if ((not items[0]) and hasattr(self, '_year_field')):
        items[0] = self._year_field.__get__(mediafile)
    items_ = []
    for item in items:
        try:
            items_.append(int(item))
        except:
            items_.append(None)
    return items_
