Cairns Photos: Bathroom snake

So I walked into a ladies toilet BUSTIN to go on the long cartrip up to cairns last holiday and OMFG. I LOOK UP AND SEE THIS HUGE BASTARD JUST LYING THERE.
for a moment I thought it was a joke rubber snake them became slightly disturbed when it moved xD Needless to say I didn't use that toilet but I did watch it for quite a while intrigued. He watched me back!

Can anyone identify this kinda Australian snake?

Photo by =Sun-Seeker