python map

Hello, I have a long and complex embedded python function. This function depends on the single rows of the input columns, so I would like to parallelize it. I’ve read about the post on embedded python and python_map. I understand that using python_map should automatically split (in a not specified way) the input columns and fire different (how many?) python processes executing on their input slice. Finally it should pack all the partial results. Well, I have tried to use python_map, but nothing different happened. Is there something more I have to do apart from setting LANGUAGE PYTHON_MAP? Regards, Stefano