Moving with snake in the winter?

I currently live on PEI, Canada, and will be moving to Halifax. Right now, the temperatures can be able -15 to -20 c, (-25 to -35) windchill. Luckily, this weekend, it is suppose to come up to between -8 and 1 degree. What is the safest way for me to transport my ball python? Anyone have any suggestions? I figured keeping a hot water bottle with my snake in some sort of container with a pillow case or something would be the best bet, but I want to make sure my ball python will be safe. The trip is about 4 hours long, so I need to be able to keep him warm for that time. IF it is not 100 percent safe for him, I will not take him. I will arrange for him to come in a few months, but this is really a last resort, as I dont want to put stress on my father to take care of him while he is busy with work.

You're going to be carrying him with you correct? Driving? So you'll be in a car where you're keeping the temps comfortable for yourself? ...if so, just pack him in an insulated box with a heat pack, same as if it's being packaged for shipment.

I would pack it in an insulated box with the proper heat pack like used to ship snakes. Then keep it with you in a heated vehicle. I don't know that its 100% safe but I think it would work. But I live in Texas so what do I know. Just my first thought.