errr....
I'm assuming you forgot to put the smileys in that post- or maybe I'm a little slow today ( it's 3.12 am and I think my brain went and hid an hour ago).
But to answer the OP's question yes they can hold their breath for a very long time indeed and it's not unusual for me to watch mine explore the underwater part of the waterbowl. One of mine even blew bubbles at me a couple of times
A vet once told me he hated trying to anaesthatise ( nope can't spell that) snakes because some of them could hold their breath for 45 minutes - which meant he couldn't be certain they were asleep if he used gas for any less time and the assistants kept assuming it had died mid procedure because it wasn't breathing at them.
dr del