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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 update(self):
 """Request an updated set of data from casper.jxml."""

        response = self.jss.session.post(self.url, data=self.auth)
        response_xml = ElementTree.fromstring(response.text.encode("utf_8"))

        # Remove previous data, if any, and then add in response's XML.
        self.clear()
        for child in response_xml.getchildren():
            self.append(child)