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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 mutect_somatic_variant_stats(variant, variant_metadata):
 """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 """


    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)