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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 get_patient_expression(job, patient_dict):
 """ Convenience function to get the expression from the patient dict :param dict patient_dict: dict of patient info :return: The gene and isoform expression :rtype: toil.fileStore.FileID """

    expression_archive = job.fileStore.readGlobalFile(patient_dict['expression_files'])
    expression_archive = untargz(expression_archive, os.getcwd())
    output_dict = {}
    for filename in 'rsem.genes.results', 'rsem.isoforms.results':
        output_dict[filename] = job.fileStore.writeGlobalFile(os.path.join(expression_archive,
                                                                           filename))
    return output_dict