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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 _extract_germline(in_file, data):
 """Extract germline calls non-somatic, non-filtered calls. """

    out_file = "%s-germline.vcf" % utils.splitext_plus(in_file)[0]
    if not utils.file_uptodate(out_file, in_file) and not utils.file_uptodate(out_file + ".gz", in_file):
        with file_transaction(data, out_file) as tx_out_file:
            reader = cyvcf2.VCF(str(in_file))
            reader.add_filter_to_header({'ID': 'Somatic', 'Description': 'Variant called as Somatic'})
            #with contextlib.closing(cyvcf2.Writer(tx_out_file, reader)) as writer:
            with open(tx_out_file, "w") as out_handle:
                out_handle.write(reader.raw_header)
                for rec in reader:
                    rec = _update_germline_filters(rec)
                    out_handle.write(str(rec))
                    #writer.write_record(rec)
    return out_file