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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 build_edges(self):
 """ Build edges based on node `edges` property. Filters out any `Edge` not defined in the DAG. """

        self.edges = [
            edge if isinstance(edge, Edge) else Edge(*edge)
            for node in self.nodes.values()
            for edge in getattr(node, "edges", [])
            if edge[0] in self.nodes and edge[1] in self.nodes
        ]
        return self