how to convince parents to let me get a bp?

[Momokahn]

Hi! So I am still relatively young, I am a 15 y/o girl and haven't finished high school yet (I'm a sophomore), and do not have a ball python yet, which I have been researching since middle school but just recently decided to ask my parents about.

My dad is pretty hesitant about it, but is still considering. On the other hand, my mom is a handful. Snakes make her skin crawl and although I've answered and rationalized all her questions, she is reluctant to let me get one (I will pay).
She is saying that since I don't really take care of the family cat that often (because she says it's supposedly my cat because I wanted it to be 'mine' when I was 10, which is easy to understand as many young children want pets to 'themselves', if you know what I mean haha). I've explained everything you need to take care of the snake and that I take care of it and I will make sure that she doesn't have to see it/the mice and rats, associate with it, or take care of it in any way (for mice and rats, I have a mini freezer in my room which I can keep them in, but she seems bothered which is confusing to me lol). However, she is still very angry at the fact I want one and doesn't believe I will be responsible for it, which I think is a bit immature on her end. Oh yeah, she thinks it smells too.
Another one of her main points is "what will you do when you go to college?", which I have already explained. I have been diagnosed with depression and anxiety, which can allow me to qualify for the snake to be an emotional support animal (ESA), which colleges are authorized to accept, with a few exceptions. All domesticated animals may qualify as an ESA, including snakes. According to the Fair Housing Act, colleges/universities must make reasonable accommodations for people with disabilities requiring ESAs. Whenever I mention this, she tries to ignore me.

How can I convince her that they aren't all that bad as she thinks they are? Please help!

It is obvious you have done your research not only for the care of a snake but also the tools (Federal Laws) you plan to use to keep a snake when you attend college. Just be aware there are wheel barrow loads of laws colleges can use to possibly keep you tied up in court instead of the classroom if wish to pursue the route you are suggesting. Going to a college campus on day one and trying to prove a point may not be the best road to travel. Going to college, getting a degree, getting your own house and then getting a snake may be the road better traveled.