code: def sample_chromosomes(job, genome_fai_file):
      
      work_dir = os.getcwd()
      genome_fai = untargz(job.fileStore.readGlobalFile(genome_fai_file), work_dir)
      return chromosomes_from_fai(genome_fai)
docs: Get a list of chromosomes in the input data.
  
      :param toil.fileStore.FileID genome_fai_file: Job store file ID for the genome fai file
      :return: Chromosomes in the sample
      :rtype: list[str]