__init__.py 文件源码

def to_python(self, value):
        if value is None:
            return value
        if isinstance(value, datetime.datetime):
            return value
        if isinstance(value, datetime.date):
            value = datetime.datetime(value.year, value.month, value.day)
            if settings.USE_TZ:
                # For backwards compatibility, interpret naive datetimes in
                # local time. This won't work during DST change, but we can't
                # do much about it, so we let the exceptions percolate up the
                # call stack.
                warnings.warn("DateTimeField %s.%s received a naive datetime "
                              "(%s) while time zone support is active." %
                              (self.model.__name__, self.name, value),
                              RuntimeWarning)
                default_timezone = timezone.get_default_timezone()
                value = timezone.make_aware(value, default_timezone)
            return value

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

        try:
            parsed = parse_date(value)
            if parsed is not None:
                return datetime.datetime(parsed.year, parsed.month, parsed.day)
        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},
        )