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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 request(self, cmds):
 """ Single Execution element is permitted. cmds can be a list or single command """

        if isinstance(cmds, list):
            cmd = '\n'.join(cmds)
        elif isinstance(cmds, str) or isinstance(cmds, unicode):
            cmd = cmds

        node = etree.Element(qualify('CLI', BASE_NS_1_0))

        etree.SubElement(node, qualify('Execution',
                                       BASE_NS_1_0)).text = cmd

        return self._request(node)