from typing import Sequence
from typing import Tuple


def my_cross_product(a: Sequence[float], b: Sequence[float]) -> Tuple[float,float,float]:
	"""
	Perform mathematical cross product between two 3D vectors.
	
	:param a: 3x float
	:param b: 3x float
	:return: 3x float
	"""
	return a[1]*b[2] - a[2]*b[1],\
		   a[2]*b[0] - a[0]*b[2],\
		   a[0]*b[1] - a[1]*b[0]