code: def _covert_to_diploid(in_file, data):
      
      sample = dd.get_sample_name(data)
      out_file = "%s-diploid.vcf" % utils.splitext_plus(in_file)[0]
      in_vcf = pysam.VariantFile(in_file)
      out_vcf = pysam.VariantFile(out_file, 'w', header=in_vcf.header)
      for record in in_vcf:
          gt = list(record.samples[sample]['GT'])
          if 'SOMATIC' in record.info:
              for allele in set(gt):
                  if allele != gt[0]:
                      record.samples[sample]['GT'] = gt[0], allele
                      out_vcf.write(record)
          else:
              if len(gt) == 1:
                  record.samples[sample]['GT'] = gt
              else:
                  record.samples[sample]['GT'] = gt[0], gt[1]
              out_vcf.write(record)
      in_vcf.close()
      out_vcf.close()
      return vcfutils.bgzip_and_index(out_file, data["config"])
docs: Converts non-diploid somatic outputs into diploid.
  
      https://github.com/luntergroup/octopus/wiki/Case-study:-Tumour-only-UMI#evaluate-variant-calls