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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_set(self, graph, orig, dest, idx, key, branch, turn, tick, value):
 """Set this key of this edge to this value."""

        if (branch, turn, tick) in self._btts:
            raise TimeError
        self._btts.add((branch, turn, tick))
        graph, orig, dest, key, value = map(self.pack, (graph, orig, dest, key, value))
        self._edgevals2set.append(
            (graph, orig, dest, idx, key, branch, turn, tick, value)
        )