Chests of logic

You are an archaeologist that has just unearthed a long sought pair of ancient treasure chests. One chest is plated with silver, and the other is plated with gold. According to legend, one of the two chests is filled with great treasure, whereas the other chest houses a man-eating python that can rip your head off. Faced with a dilemma, you then notice that there are inscriptions on the chests:

Silver Chest: This chest contains the python.

Gold Chest: Exactly one of these two inscriptions is true.

Which should you open?

Variation

Same story, but this time all you know is that in each chest there is either a treasure or a man eating snake. You know that either both boxes are true, or both are false. The chests read:

Silver chest: At least one of these boxes contains a treasure

Gold chest: The silver chest contains a man eating snake.

Which should you open?