How to put model entities into a group using Python API?

Dear Sim4life Team,
I have created an EntityGroup and some entities using Python API scripter, but I don't know how to put these entities into this EntityGroup using Python API. Could you help me answer this question?

Thank you!
Mingjuan Ma

Something like this

my_group = s4l.model.CreateGroup()
my_poly = s4l.model.CreatePolyLine(my_points)
my_group.Add(my_poly)