def METHOD_NAME(self, octupole_knob, p0):
    i_octupole_focusing = 19.557 * (octupole_knob / -1.5
                                    * p0 / 2.4049285931335872e-16)
    i_octupole_defocusing = -i_octupole_focusing
    return i_octupole_focusing, i_octupole_defocusing