Wow what a stunning snake, unsure of what type it is, I thought Jungle at first but your location :/ Hmm I am no expert obviously but I agree with Darlyn on this one.
My mistake, was viewing this thread from my phone at the time and wasn't sure if it was a captive or not. Interesting pattern on it for a Darwin though! Any more pictures, some in sunlight?
Younger ones don't have the orange colour. That comes later as they age.
The back part colours up first so the one I'm holding is just starting to colour up now. (SteveNT's pic)
This pic shows that she is the same colour all the way thru (kinda)