tunnel runner tutorials- stuck with action actuator

in the tutorial an f-curve is used, so i used to an action actuator in its place, however, i dont know how to script it to work with the action actuator, help is appreciated.
Im on this section of the series :

and here is the .blend file

Tunnel Runner.blend (461 KB)

Here is the code in code blocks:

from bge import logic
import random

def _positionNewBlock(new_block, block):
    AXIS = 0 # X
    if block.name[0] == "H":
        AXIS = 2 # Z
    rand_range = block.worldPosition[AXIS]
    rand = random.uniform(-rand_range, rand_range)
    new_block.worldPosition[AXIS] = rand 

def _fireObjects(list_objects, speed):
    for gobj in list_objects:
        gobj.setLinearVelocity([0, -speed, 0])

def _setFrameRange(new_block):
    left = (0, 40)
    right = (40, 80)
    frame_range = random.choice((left, right))
    Action = new_block.actuators["Crusher"]
    Crusher.frameStart = frame_range[0]
    Crusher.frameEnd = frame_range[1]
def spawn():
    scene = logic.getCurrentScene()
    blocks = (scene.objects["H_Block"], scene.objects["V_Block"],/
    block = random.choice(blocks)
    new_block = scene.addObject(block, scene.objects["Spawner"])
    _positionNewBlock(new_block, block)
    if "Slider" in new_block.name:
    brace = scene.addObject(scene.objects["Brace"], scene.objects["Spawner"])
    objects = (new_block, brace)
    _fireObjects(objects, 180)

p.s i know about the variable being named Action and me calling it as Crusher, thats not the problem though, just a mistake i forgot to fix when playing around!