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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 close_node(self, node_id, *args, **kwargs):
 """ Closes a VPCS VM. :returns: VPCSVM instance """


        node = self.get_node(node_id)
        if node_id in self._used_mac_ids:
            i = self._used_mac_ids[node_id]
            self._free_mac_ids[node.project.id].insert(0, i)
            del self._used_mac_ids[node_id]
        yield from super().close_node(node_id, *args, **kwargs)
        return node