I used to work for Petco, in the animal departments, and the snakes in that display were probably extremely stressed. At any given point at least half of the snakes on the floor weren't eating, and we often lost corn snakes that would simply never eat. Often the store had bouts of mites (so getting a new snake and putting it in with yours might give you a massive case of them) and not everyone there knew much about the animals, and so made up information that they told customers. If I didn't clean the cages, often the other people would just cover up the poop with new bedding - it looked clean, but really wasn't. Easily could have led to scale rot or any number of diseases.
It might look like the snakes are all doing fine, but chances are they're not. I purchased one of my own snakes from the store I worked for (she was pretty!) and she began eating immediately once she had her own cage.
Like everyone else has said, never house two different species of snakes together, especially not boas and pythons. Your snake is nice and tame with you, but you are not a snake. You can't apply how it behaves with you to how it'll behave with another reptile.
Enjoy your ball!
~jenny
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"The python has, and I fib no fibs,
318 pairs of ribs.
In stating this I place reliance
On a seance with one who died for science
This figure is sworn to and attested,
He counted them while being digested."
~Ogden Nash
jenny.thegreenes.org
"If you're happy and you know it,
Bomb Iraq!
If you cannot find Osama,
Bomb Iraq!
If the terrorists are frisky,
Pakistan is looking shifty,
North Korea is too risky,
Bomb Iraq!
