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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def attach(cls, transform_job_name, sagemaker_session=None):
 """Attach an existing transform job to a new Transformer instance Args: transform_job_name (str):
 Name for the transform job to be attached. sagemaker_session (sagemaker.session.Session):
 Session object which manages interactions with Amazon SageMaker APIs and any other AWS services needed. If not specified, one will be created using the default AWS configuration chain. Returns: sagemaker.transformer.Transformer: The Transformer instance with the specified transform job attached. """

        sagemaker_session = sagemaker_session or Session()

        job_details = sagemaker_session.sagemaker_client.describe_transform_job(TransformJobName=transform_job_name)
        init_params = cls._prepare_init_params_from_job_description(job_details)
        transformer = cls(sagemaker_session=sagemaker_session, **init_params)
        transformer.latest_transform_job = _TransformJob(sagemaker_session=sagemaker_session,
                                                         job_name=init_params['base_transform_job_name'])

        return transformer