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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 _add_somatic_opts(opts, paired):
 """Add somatic options to current set. See _run_freebayes_paired for references. """

    if "--min-alternate-fraction" not in opts and "-F" not in opts:
        # add minimum reportable allele frequency
        # FreeBayes defaults to 20%, but use 10% by default for the
        # tumor case
        min_af = float(utils.get_in(paired.tumor_config, ("algorithm",
                                                          "min_allele_fraction"), 10)) / 100.0
        opts += " --min-alternate-fraction %s" % min_af
    # Recommended settings for cancer calling
    opts += (" --pooled-discrete --pooled-continuous "
             "--report-genotype-likelihood-max --allele-balance-priors-off")
    return opts