from typing import Tuple


def lorenz_step(start_pt: Tuple[int, int, int], s=10, b=2.667, r=28):
    """
    :param start_pt: starting point in 3-dimensional space
    :param s, r, b: parameters of the Lorenz attractor (usually indicated with the Greek letters sigma, ro, beta)
    :returns: x_dot, y_dot, z_dot: values of the lorenz attractor's partial derivatives at the point start_pt
    """
    # break down the starting point start_pt into 3 variables representing a dimension each, for simplicity
    x, y, z = start_pt[0], start_pt[1], start_pt[2]
    x_dot = s * (y - x)
    y_dot = r * x - y - x * z
    z_dot = x * y - b * z
    return x_dot, y_dot, z_dot