def prepare_container_def(self, instance_type, accelerator_type=None):  # pylint disable=unused-argument
        """Return a container definition with framework configuration set in model environment variables.

        This also uploads user-supplied code to S3.

        Args:
            instance_type (str): The EC2 instance type to deploy this Model to. For example, 'ml.p2.xlarge'.
            accelerator_type (str): The Elastic Inference accelerator type to deploy to the instance for loading and
                making inferences to the model. For example, 'ml.eia1.medium'.

        Returns:
            dict[str, str]: A container definition object usable with the CreateModel API.
        """
        deploy_key_prefix = fw_utils.model_code_key_prefix(self.key_prefix, self.name, self.image)
        self._upload_code(deploy_key_prefix)
        deploy_env = dict(self.env)
        deploy_env.update(self._framework_env_vars())
        return sagemaker.container_def(self.image, self.model_data, deploy_env)