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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 _set_persistent_boot(self, values=[]):
 """Configures a boot from a specific device."""


        xml = self._create_dynamic_xml(
            'SET_PERSISTENT_BOOT', 'SERVER_INFO', 'write')

        if six.PY2:
            child_iterator = xml.getiterator()
        else:
            child_iterator = xml.iter()

        for child in child_iterator:
            for val in values:
                if child.tag == 'SET_PERSISTENT_BOOT':
                    etree.SubElement(child, 'DEVICE', VALUE=val)
        d = self._request_ilo(xml)
        data = self._parse_output(d)
        return data