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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 node_insert_after(self, node, new_node):
 """Insert the new node after node."""


        assert(not self.node_is_on_list(new_node))
        assert(node is not new_node)

        next = self.node_next(node)
        assert(next is not None)
        self.node_set_next(node, new_node)
        self.node_set_prev(new_node, node)

        self.node_set_next(new_node, next)
        self.node_set_prev(next, new_node)