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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 to_html_(self) -> str: """Convert the main dataframe to html :return: html data :rtype: str :example: ``ds.to_html_()`` """

        try:
            renderer = pytablewriter.HtmlTableWriter
            data = self._build_export(renderer)
            return data
        except Exception as e:
            self.err(e, "Can not convert data to html")