def acquire(self, blocking=1):
        rc = False
        self.__cond.acquire()
        while self.__value == 0:
            if not blocking:
                break
            if __debug__:
                self._note("%s.acquire(%s): blocked waiting, value=%s",
                           self, blocking, self.__value)
            self.__cond.wait()
        else:
            self.__value = 1 - self.__value
            if __debug__:
                self._note("%s.acquire: success, value=%s",
                           self, self.__value)
            rc = True
        self.__cond.release()
        return rc
dataset/ETHPy150Open deanhiller/databus/webapp/play1.3.x/python/Lib/threading.py/_Semaphore.acquire/swapped operands of `-`