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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 result(self):
 """ Returns the result from the worker for this job. This is used to pass result in async way. """

        if self.__result:
            return self.__result
        data = self.rdb.rpop(self.urn)
        if data:
            self.rdb.delete(self.urn)
            data = json.loads(data)
            self.__result = data
            return data
        else:
            return None