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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 compute_rpo(self):
 """ Number the nodes in reverse post order. An RPO traversal visit as many predecessors of a node as possible before visiting the node itself. """

        nb = len(self.nodes) + 1
        for node in self.post_order():
            node.num = nb - node.po
        self.rpo = sorted(self.nodes, key=lambda n: n.num)