<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def run_radia_perchrom(job, bams, univ_options, radia_options, chrom):
 """ Run RADIA call on a single chromosome in the input bams. :param dict bams: Dict of bam and bai for tumor DNA-Seq, normal DNA-Seq and tumor RNA-Seq :param dict univ_options: Dict of universal options used by almost all tools :param dict radia_options: Options specific to RADIA :param str chrom: Chromosome to process :return: fsID for the chromsome vcf :rtype: toil.fileStore.FileID """

    work_dir = os.getcwd()
    input_files = {
        'rna.bam': bams['tumor_rna'],
        'rna.bam.bai': bams['tumor_rnai'],
        'tumor.bam': bams['tumor_dna'],
        'tumor.bam.bai': bams['tumor_dnai'],
        'normal.bam': bams['normal_dna'],
        'normal.bam.bai': bams['normal_dnai'],
        'genome.fa.tar.gz': radia_options['genome_fasta'],
        'genome.fa.fai.tar.gz': radia_options['genome_fai']}
    input_files = get_files_from_filestore(job, input_files, work_dir, docker=False)

    for key in ('genome.fa', 'genome.fa.fai'):
        input_files[key] = untargz(input_files[key + '.tar.gz'], work_dir)
    input_files = {key: docker_path(path) for key, path in input_files.items()}

    radia_output = ''.join([work_dir, '/radia_', chrom, '.vcf'])
    radia_log = ''.join([work_dir, '/radia_', chrom, '_radia.log'])
    parameters = [univ_options['patient'],  # shortID
                  chrom,
                  '-n', input_files['normal.bam'],
                  '-t', input_files['tumor.bam'],
                  '-r', input_files['rna.bam'],
                  ''.join(['--rnaTumorFasta=', input_files['genome.fa']]),
                  '-f', input_files['genome.fa'],
                  '-o', docker_path(radia_output),
                  '-i', univ_options['ref'],
                  '-m', input_files['genome.fa'],
                  '-d', 'aarjunrao@soe.ucsc.edu',
                  '-q', 'Illumina',
                  '--disease', 'CANCER',
                  '-l', 'INFO',
                  '-g', docker_path(radia_log)]
    docker_call(tool='radia', tool_parameters=parameters,
                work_dir=work_dir, dockerhub=univ_options['dockerhub'],
                tool_version=radia_options['version'])
    output_file = job.fileStore.writeGlobalFile(radia_output)
    job.fileStore.logToMaster('Ran radia on %s:%s successfully' % (univ_options['patient'], chrom))
    return output_file