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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 convert_html_to_xml(self):
 """ Parses the HTML parsed texts and converts its tags to XML valid tags. :returns: HTML enabled text in a XML valid format. :rtype: str """


        if hasattr(self, 'content') and self.content != '':
            regex = r'<(?!/)(?!!)'
            xml_content = re.sub(regex, '<xhtml:', self.content)
            return xml_content
        else:
            return ''