My usual advice is small, short handling sessions and/or having them just get used to your scent and all that fun stuff but sometimes you just get a spitfire animal with a bad attitude.

The most aggressive animal I have ever owned was a ball python that would viciously strike at me any time I so much as passed by her tub. Feeding time involved cracking it open and tossing the rat in super quick then closing it. Checking temperatures and changing water every day was a nightmare and I can't even begin to tell you how many times I'd been bitten.

I got the temperament of an angry wasp nest in a 3 pound ball python! Sometimes it just happens.

If temps and umidity are correct and this animal is a rescue, have you gotten her checked out by a vet? there might be another issue causing her stress and discomfort enough to make her act so wiley.