Message3565

The cause here is PyTypeDerived#__repr__ looking up for the  "__repr__"
entry on its type and finding the one exposed by PyObject.

I think we will have to check if the type that exposed __repr__ is down
in the type hierarchy or not. In the later case, we should call super()
instead of the exposed __repr__().  Another possibility would be to
actually expose __repr__ on PyType, but that would mean that we should
do the same with every type implementing toString().