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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 fulfill(self):
 """ Evaluate the promise and return the result. Returns: The result of the `Promise` (second return value from the `check_func`) Raises: BrokenPromise: the `Promise` was not satisfied within the time or attempt limits. """

        is_fulfilled, result = self._check_fulfilled()

        if is_fulfilled:
            return result
        else:
            raise BrokenPromise(self)