How to do an update + join in PostgreSQL?

Basically, I want to do this:

update vehicles_vehicle v     join shipments_shipment s on v.shipment_id=s.id set v.price=s.price_per_vehicle;

I'm pretty sure that would work in MySQL (my background), but it doesn't seem to work in postgres. The error I get is:

ERROR:  syntax error at or near "join"LINE 1: update vehicles_vehicle v join shipments_shipment s on v.shi...                                  ^

Surely there's an easy way to do this, but I can't find the proper syntax. So, how would I write this In PostgreSQL?