You will likely find plastic so much easier than glass for ball pythons. With their need for very specific temps and humidity it really is the way to go in my opinion. We have 13 ball pythons of various ages living quite happily in their plastic homes.

You can either drill or melt vent holes in the plastic. If melting use a simple soldering wand ($6.00 at WalMart) in a well ventilated area. If drilling be careful to not split the tub or lid. Start with some holes in the lid and around the sides and see how the tub does. Put the heat under it, papertowels, hides and a full water dish on the cool side, plus the Acu-Rite and let it all sit for a few hours or a day...then you will see if you need to add more holes and get it stable before you move the snake in.

If you have an OfficeMax handy to you I'd advise you to go there and buy an Iris brand tub. They are only a few dollars more than Sterlite or Rubbermaid but in my opinion a far better quality and glass quality clear. You will need to buy some large binder clips however to make any plastic storage lid snake proof (anything more than a 1/8 inch give and your snake can squeeze out). You don't want a high tub, think floor space more than height for ball pythons.