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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 run_coral(clus_obj, out_dir, args):
 """ Run some CoRaL modules to predict small RNA function """

    if not args.bed:
        raise ValueError("This module needs the bed file output from cluster subcmd.")
    workdir = op.abspath(op.join(args.out, 'coral'))
    safe_dirs(workdir)
    bam_in = op.abspath(args.bam)
    bed_in = op.abspath(args.bed)
    reference = op.abspath(args.ref)
    with chdir(workdir):
        bam_clean = coral.prepare_bam(bam_in, bed_in)
        out_dir = op.join(workdir, "regions")
        safe_dirs(out_dir)
        prefix = "seqcluster"
        loci_file = coral.detect_regions(bam_clean, bed_in, out_dir, prefix)
        coral.create_features(bam_clean, loci_file, reference, out_dir)