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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_elem(self, netapp_api=None, sub_element=None):
 """ Retrieve netapp elem """


        netapp_data = self.server.invoke_elem(netapp_api)

        if netapp_data.results_status() == 'failed':
            self.log.error(
                'While using netapp API failed to retrieve '
                'disk-list-info for netapp filer %s' % self.device)
            print(netapp_data.sprintf())
            return
        netapp_xml = \
            ET.fromstring(netapp_data.sprintf()).find(sub_element)

        return netapp_xml