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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 stop(self):
 """Output Checkstyle XML reports."""

        et = ET.ElementTree(self.checkstyle_element)
        f = BytesIO()
        et.write(f, encoding='utf-8', xml_declaration=True)
        xml = f.getvalue().decode('utf-8')
        if self.output_fd is None:
            print(xml)
        else:
            self.output_fd.write(xml)
        super(CheckstylePlugin, self).stop()