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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 _handle_somatic_ensemble(vrn_file, data):
 """For somatic ensemble, discard normal samples and filtered variants from vcfs. Only needed for bcbio.variation based ensemble calling. """

    if tz.get_in(["metadata", "phenotype"], data, "").lower().startswith("tumor"):
        vrn_file_temp = vrn_file.replace(".vcf", "_tumorOnly_noFilteredCalls.vcf")
        # Select tumor sample and keep only PASS and . calls
        vrn_file = vcfutils.select_sample(in_file=vrn_file, sample=data["name"][1],
                                          out_file=vrn_file_temp,
                                          config=data["config"], filters="PASS,.")
    return vrn_file