def _mkref(self, obj):
        obj_id = id(obj)
        try:
            self._obj_to_idx[obj_id]
        except __HOLE__:
            self._obj_to_idx[obj_id] = len(self._objs)
            self._objs.append(obj)
            # Backwards compatibility: old versions of jsonpickle
            # produced "py/ref" references.
            self._namedict[self._refname()] = obj
        return obj
dataset/ETHPy150Open jsonpickle/jsonpickle/jsonpickle/unpickler.py/Unpickler._mkref