I am struggling to add indicator and SOS constraints using mathopt library in or-tools. In the web-page it is mentioned that mathopt supports these specialised constraints, but I am not able to use them in my program.
Below is a small dummy code, through which I want to use these constraints.

I have 160 players signed up for a baseball league age group. I want to have exactly 16 teams of 10 players. Each team starts with an assigned Head coach and the coach’s son, so that leaves 144 more players to assign. The players are have 5 optional fields they can fill out for special requests: coach, friend 1, friend 2, friend 3, their school,