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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 _generate_index(root, folder, paths, bots_index=False, bots_index_paths=()):
 """Generates the index file for the specified folder"""

    # Determine the namespaces listed here (as sub folders)
    # and the files (.html files) that we should link to
    namespaces = []
    files = []
    INDEX = 'index.html'
    BOT_INDEX = 'botindex.html'

    for item in (bots_index_paths or folder.iterdir()):
        if item.is_dir():
            namespaces.append(item)
        elif item.name not in (INDEX, BOT_INDEX):
            files.append(item)

    # Now that everything is setup, write the index.html file
    filename = folder / (BOT_INDEX if bots_index else INDEX)
    with DocsWriter(root, filename, _get_path_for_type) as docs:
        # Title should be the current folder name
        docs.write_head(str(folder).replace(os.path.sep, '/').title(),
                        css_path=paths['css'],
                        default_css=paths['default_css'])

        docs.set_menu_separator(paths['arrow'])
        _build_menu(docs)
        docs.write_title(str(filename.parent.relative_to(root))
                         .replace(os.path.sep, '/').title())

        if bots_index:
            docs.write_text('These are the methods that you may be able to '
                            'use as a bot. Click <a href="{}">here</a> to '
                            'view them all.'.format(INDEX))
        else:
            docs.write_text('Click <a href="{}">here</a> to view the methods '
                            'that you can use as a bot.'.format(BOT_INDEX))
        if namespaces:
            docs.write_title('Namespaces', level=3)
            docs.begin_table(4)
            namespaces.sort()
            for namespace in namespaces:
                # For every namespace, also write the index of it
                namespace_paths = []
                if bots_index:
                    for item in bots_index_paths:
                        if item.parent == namespace:
                            namespace_paths.append(item)

                _generate_index(root, namespace, paths,
                                bots_index, namespace_paths)

                docs.add_row(
                    namespace.stem.title(),
                    link=namespace / (BOT_INDEX if bots_index else INDEX))

            docs.end_table()

        docs.write_title('Available items')
        docs.begin_table(2)

        files = [(f, _find_title(f)) for f in files]
        files.sort(key=lambda t: t[1])

        for file, title in files:
            docs.add_row(title, link=file)

        docs.end_table()
        docs.end_body()