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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 toc_directive(self, maxdepth=1):
 """ Generate toctree directive text. :param table_of_content_header: :param header_bar_char: :param header_line_length: :param maxdepth: :return: """

        articles_directive_content = TC.toc.render(
            maxdepth=maxdepth,
            article_list=self.sub_article_folders,
        )
        return articles_directive_content