def vecCrossProduct(vec1, vec2):
    """The vector cross product (in 3d).

    >>> vecCrossProduct((1,0,0),(0,1,0))
    (0, 0, 1)
    >>> vecCrossProduct((1,2,3),(4,5,6))
    (-3, 6, -3)
    """
    return (vec1[1] * vec2[2] - vec1[2] * vec2[1],
            vec1[2] * vec2[0] - vec1[0] * vec2[2],
            vec1[0] * vec2[1] - vec1[1] * vec2[0])