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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 serialize(self, content):
 """ Serialize to xml. :return string: """

        return self.xmldoc_tpl % (
            'true' if self.response.status_code == HTTP_200_OK else 'false',
            str(self.resource.api or ''),
            int(mktime(datetime.now().timetuple())),
            super(XMLTemplateEmitter, self).serialize(content)
        )