Where's coolant bleeder valve prius 2016?

I see there're two versions of coolant reservoir one with air release valve and one without. And I don't see 6mm hex for my prius 2016's reservoir. How do I bleed air from the one that doesn't have? Is it somewhere over radiator like in 2nd gen but I don't see any hole with a coolant release warning there.
I've 2 day subscription from techinfo but can't find it from there too, and i'm using the website for the first time.