def add(self, key):
        if self.map not in key:
            end = self.end
            curr = end[1]
            curr[2] = end[1] = self.map[key] = [key, curr, end]
dataset/ETHPy150Open ioflo/ioflo/ioflo/aid/osetting.py/oset.add/swapped operands of `not in`