synchronized lists

[Andreas Kremer]

Hi,

> Making pointers to and from is messy and a usual source of cyclic
> references. Combined with using __del__, this will result in "memory
> leaks", IIRC.

Thanks. Actually this is the reason why i am thinking of secure mechanismn
which avoids cyclic references or at least removes all references of objects
towards each other, if one object is deleted.