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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 compare_variants_label_plot(data):
 """ Return HTML for the Compare variants plot"""

    keys = OrderedDict()

    keys['total_called_variants_known'] = {'name': 'Known Variants'}
    keys['total_called_variants_novel'] = {'name': 'Novel Variants'}

    pconfig = {
        'id': 'picard_variantCallingMetrics_variant_label',
        'title': 'Picard: Variants Called',
        'ylab': 'Counts of Variants',
     }

    return bargraph.plot(data, cats=keys, pconfig=pconfig)