How to access the weight of Constraints of a Rig (Animation Rigging Package)

I am trying to control the weight of each constraint that a Rig has and I can't figure it out through code, I tried using GetChild(Index of the constraint here) but its not working. I also tried doing the usual serialized private Gameobject and just dragging and dropping the constraint there, that works but how to do it through code? without dragging and dropping in the inspector.