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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 run(align_bams, items, ref_file, assoc_files, region, out_file):
 """Return DeepVariant calling on germline samples. region can be a single region or list of multiple regions for multicore calling. """

    assert not vcfutils.is_paired_analysis(align_bams, items), \
        ("DeepVariant currently only supports germline calling: %s" %
         (", ".join([dd.get_sample_name(d) for d in items])))
    assert len(items) == 1, \
        ("DeepVariant currently only supports single sample calling: %s" %
         (", ".join([dd.get_sample_name(d) for d in items])))
    out_file = _run_germline(align_bams[0], items[0], ref_file,
                             region, out_file)
    return vcfutils.bgzip_and_index(out_file, items[0]["config"])