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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 get_netapp_data(self):
 """ Retrieve netapp volume information returns ElementTree of netapp volume information """


        netapp_data = self.server.invoke('volume-list-info')

        if netapp_data.results_status() == 'failed':
            self.log.error(
                'While using netapp API failed to retrieve '
                'volume-list-info for netapp filer %s' % self.device)
            return

        netapp_xml = ET.fromstring(netapp_data.sprintf()).find('volumes')

        return netapp_xml