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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):
 """Render a Text MessageElement as html Args: None Returns: Str the html representation of the Text MessageElement Raises: Errors are propagated """

        if self.items is None:
            return
        else:
            html = '<ol%s>\n' % self.html_attributes()
            for item in self.items:
                html += '<li>%s</li>\n' % item.to_html()
            html += '</ol>'
            return html