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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 reciprocal(self):
 """If there's another Portal connecting the same origin and destination that I do, but going the opposite way, return it. Else raise KeyError. """

        try:
            return self.character.portal[self.dest][self.orig]
        except KeyError:
            raise KeyError("This portal has no reciprocal")