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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 edge_val_dump(self):
 """Yield the entire contents of the edge_val table."""

        self._flush_edge_val()
        for (
                graph, orig, dest, idx, key, branch, turn, tick, value
        ) in self.sql('edge_val_dump'):
            yield (
                self.unpack(graph),
                self.unpack(orig),
                self.unpack(dest),
                idx,
                self.unpack(key),
                branch,
                turn,
                tick,
                self.unpack(value)
            )