Assemble a mutiblock in parallel

Hi ParaView crew,

Is it possible to perform any kind of multiprocessing with a programmable filter?

I am trying out to use a ProcessingPool from pathos:

but I am getting into the pickling nightmare (e.g.):
TypeError: cannot pickle ‘paraview.modules.vtkRemotingServerManager.vtkSMSession’ object

My goal would be read from file hundreds of blocks and put them in a vtkMultiBlockDataSet to return back to ParaView. Any hint for doing this?

Thank you