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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 wrap_rsem(job, star_bams, univ_options, rsem_options):
 """ A wrapper for run_rsem using the results from run_star as input. :param dict star_bams: dict of results from star :param dict univ_options: Dict of universal options used by almost all tools :param dict rsem_options: Options specific to rsem :return: Dict of gene- and isoform-level expression calls output_files: |- 'rsem.genes.results': fsID +- 'rsem.isoforms.results': fsID :rtype: dict """

    rsem = job.addChildJobFn(run_rsem, star_bams['rna_transcriptome.bam'],
                             univ_options, rsem_options, cores=rsem_options['n'],
                             disk=PromisedRequirement(rsem_disk, star_bams,
                                                      rsem_options['index']))

    return rsem.rv()