__init__.py 文件源码

def to_python(self, value):
        if value is None:
            return value
        if isinstance(value, datetime.datetime):
            if settings.USE_TZ and timezone.is_aware(value):
                # Convert aware datetimes to the default time zone
                # before casting them to dates (#17742).
                default_timezone = timezone.get_default_timezone()
                value = timezone.make_naive(value, default_timezone)
            return value.date()
        if isinstance(value, datetime.date):
            return value

        try:
            parsed = parse_date(value)
            if parsed is not None:
                return parsed
        except ValueError:
            raise exceptions.ValidationError(
                self.error_messages['invalid_date'],
                code='invalid_date',
                params={'value': value},
            )

        raise exceptions.ValidationError(
            self.error_messages['invalid'],
            code='invalid',
            params={'value': value},
        )