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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 execute(self):
 """ Execute all of the saved commands and return results. """

        try:
            for key, value in self._watched_keys.items():
                if self.mock_redis.redis.get(self.mock_redis._encode(key)) != value:
                    raise WatchError("Watched variable changed.")
            return [command() for command in self.commands]
        finally:
            self._reset()