Bertotti Losses distribution in Flux2D Thermal simulation

Hello, 

I am performing thermal simulation using Flux2D and I want to import Bertotti losses distribution from magnetostatic model using Python script. When I run the .py script I receive the following error:

Unknown argument: Bertotti_losses_distribution_stator_lamination_2D

This argument must be defined in your jython session before usage.

Do you have any idea about that? Could you help me, please? Thanks.