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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 terminate(self, nodes=None):
 """Destroy one or many nodes. :param nodes: Nodes to be destroyed. :type nodes: ``list`` :return: List of nodes which failed to terminate. :rtype: ``list`` """

        if not self.is_connected():
            return None

        nodes = nodes or self.nodes
        failed_kill = []

        result = self.gce.ex_destroy_multiple_nodes(nodes, poll_interval=1, ignore_errors=False)

        # Verify whether all instances have been terminated.
        for i, success in enumerate(result):
            if success:
                logging.info('Successfully destroyed: %s', nodes[i].name)
            else:
                logging.error('Failed to destroy: %s', nodes[i].name)
                failed_kill.append(nodes[i])

        return failed_kill