datetime.py 文件源码

def convert_value(self, value, expression, connection, context):
        if isinstance(self.output_field, DateTimeField):
            if settings.USE_TZ:
                if value is None:
                    raise ValueError(
                        "Database returned an invalid datetime value. "
                        "Are time zone definitions for your database and pytz installed?"
                    )
                value = value.replace(tzinfo=None)
                value = timezone.make_aware(value, self.tzinfo)
        elif isinstance(value, datetime):
            if isinstance(self.output_field, DateField):
                value = value.date()
            elif isinstance(self.output_field, TimeField):
                value = value.time()
        return value