How to get long term and short term background model

Hi:
I'm using the python wrapper of bgslibrary on Ubuntu 18.04 now.
In demo2.py, the bgmodel is generated by algorithm.getBackgroundModel(). However, I want to get a short term and a long term background model now. Which is similar to the opencv function shown in img 2. In opencv, I can set different learning rate. Does there any parameter in bgslibrary python that I can change?
Thank you so much!