def __deepcopy__(self, memo):
        out = SON()
        val_id = id(self)
        if memo in val_id:
            return memo.get(val_id)
        memo[val_id] = out
        for k, v in self.iteritems():
            if not isinstance(v, RE_TYPE):
                v = copy.deepcopy(v, memo)
            out[k] = v
        return out
dataset/ETHPy150Open OpenMDAO/OpenMDAO-Framework/openmdao.lib/src/openmdao/lib/casehandlers/pymongo_bson/son.py/SON.__deepcopy__/swapped operands of `in`