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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):
 """ Close a node :param node_id: Node identifier :returns: Node instance """


        node = self.get_node(node_id)
        if asyncio.iscoroutinefunction(node.close):
            yield from node.close()
        else:
            node.close()
        return node