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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 html(self, text=TEXT):
 """ Generate an HTML file from the report data. """

        self.logger.debug("Generating the HTML report{}..."
                          .format(["", " (text only)"][text]))
        html = []
        for piece in self._pieces:
            if isinstance(piece, string_types):
                html.append(markdown2.markdown(piece, extras=["tables"]))
            elif isinstance(piece, Element):
                html.append(piece.html())
        return "\n\n".join(html)