When I'm trying to unpickle an instance object I get a class cast exception saying:
java.lang.ClassCastException: org.python.core.PyObjectDerived
	at org.python.modules.cPickle$Unpickler.load_build(cPickle.java)

This happens at the below line in this function:
        final private void load_build() {
            ...
            PyInstance inst  = (PyInstance)peek();
        
looks like there is something of type PyObjectDervice on the stack which isn't a 'PyInstance'.


The python part is An class object in module a.b.c of Type X.  It has the attributes 'name','asof','data'.  name is a string, asof is None and data is an empty list.

The pickle string is:

ccopy_reg
_reconstructor
p1
(ca.b.c
X
p2
c__builtin__
object
p3
NtRp4
(dp5
S'data'
p6
(lp7
sS'name'
p8
S'Current'
p9
sS'asof'
p10
Nsb.