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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 iter_successors(self, graph, orig, branch, turn, tick, *, forward=None):
 """Iterate over successors of a given origin node at a given time."""

        if self.db._no_kc:
            yield from self._adds_dels_sucpred(self.successors[graph, orig], branch, turn, tick)[0]
            return
        if forward is None:
            forward = self.db._forward
        yield from self._get_destcache(graph, orig, branch, turn, tick, forward=forward)