code: def mutect_somatic_variant_stats(variant, variant_metadata):
      
  
      sample_info = variant_metadata["sample_info"]
      # Ensure there are exactly two samples in the VCF, a tumor and normal
      assert len(sample_info) == 2, "More than two samples found in the somatic VCF"
  
      # Find the sample with the genotype field set to variant in the VCF
      tumor_sample_infos = [info for info in sample_info.values() if info["GT"] == "0/1"]
  
      # Ensure there is only one such sample
      assert len(tumor_sample_infos) == 1, "More than one tumor sample found in the VCF file"
  
      tumor_sample_info = tumor_sample_infos[0]
      normal_sample_info = [info for info in sample_info.values() if info["GT"] != "0/1"][0]
  
      tumor_stats = _mutect_variant_stats(variant, tumor_sample_info)
      normal_stats = _mutect_variant_stats(variant, normal_sample_info)
      return SomaticVariantStats(tumor_stats=tumor_stats, normal_stats=normal_stats)
docs: Parse out the variant calling statistics for a given variant from a Mutect VCF
  
      Parameters
      ----------
      variant : varcode.Variant
      sample_info : dict
          Dictionary of sample to variant calling statistics, corresponds to the sample columns
          in a Mutect VCF
  
      Returns
      -------
      SomaticVariantStats