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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 split_somatic(items):
 """Split somatic batches, adding a germline target. Enables separate germline calling of samples using shared alignments. """

    items = [_clean_flat_variantcaller(x) for x in items]
    somatic_groups, somatic, non_somatic = vcfutils.somatic_batches(items)
    # extract germline samples to run from normals in tumor/normal pairs
    germline_added = set([])
    germline = []
    for somatic_group in somatic_groups:
        paired = vcfutils.get_paired(somatic_group)
        if paired and paired.normal_data:
            cur = utils.deepish_copy(paired.normal_data)
            vc = dd.get_variantcaller(cur)
            if isinstance(vc, dict) and "germline" in vc:
                if cur["description"] not in germline_added:
                    germline_added.add(cur["description"])
                    cur["rgnames"]["sample"] = cur["description"]
                    cur["metadata"]["batch"] = "%s-germline" % cur["description"]
                    cur["metadata"]["phenotype"] = "germline"
                    cur = remove_align_qc_tools(cur)
                    cur["config"]["algorithm"]["variantcaller"] = vc["germline"]
                    germline.append(cur)
    # Fix variantcalling specification for only somatic targets
    somatic_out = []
    for data in somatic:
        vc = dd.get_variantcaller(data)
        if isinstance(vc, dict) and "somatic" in vc:
            data["config"]["algorithm"]["variantcaller"] = vc["somatic"]
        somatic_out.append(data)
    return non_somatic + somatic_out + germline