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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 correlation(args):
 """ %prog correlation postgenomic-s.tsv Plot correlation of age vs. postgenomic features. """

    p = OptionParser(correlation.__doc__)
    opts, args, iopts = p.set_image_options(args, figsize="12x8")

    if len(args) != 1:
        sys.exit(not p.print_help())

    tsvfile, = args
    df = pd.read_csv(tsvfile, sep="\t")
    composite_correlation(df, size=(iopts.w, iopts.h))
    outfile = tsvfile.rsplit(".", 1)[0] + ".correlation.pdf"
    savefig(outfile)