I had 2 snakes.
3' male Ball Python and a 7' Boa Constrictor. The Boa I had since it was the size of my little finger and the Python came straight from Africa.
Avoid putting your hand in the cage when they're feeding. I had both snakes in one cage and usually feed them at the same time, but the Boa became larger than the python and started to go after it when it had a mouse in it's mouth. Needless to say, I got hit on the hand by the Boa. It felt like a blow from a checkered-face framing hammer.