def METHOD_NAME():
    '''
    Build dict of unicode categories e.g.
    {
        'Lu': ['A', 'B', 'C', ...]
        'Ll': ['a', 'b', 'c', ...]
    }
    '''
    categories = defaultdict(list)
    for row in parse_unicode_data():
        categories[row.category].append(wide_unichr(unicode_to_integer(row.code)))
    return dict(categories)