How to use the simgrid.this_actor.get_host function in simgrid

def __call__(self):
        computation_amount = this_actor.get_host().speed
        this_actor.info("Execute {:.0f} flops, should take 1 second.".format(computation_amount))
        activity = this_actor.exec_init(computation_amount).start()

        this_actor.sleep_for(0.5)
        this_actor.info("I changed my mind, cancel!")
        activity.cancel()

        this_actor.info("Goodbye now!")

def __call__(self):
        computation_amount = this_actor.get_host().speed
        this_actor.info("Execute {:.0f} flops, should take 1 second.".format(computation_amount))
        activity = this_actor.exec_init(computation_amount).start()

        while not activity.test():
            this_actor.info("Remaining amount of flops: {:.0f} ({:.0f}%)".format(
                activity.remaining, 100 * activity.remaining_ratio))
            this_actor.sleep_for(0.3)
        activity.wait()

        this_actor.info("Goodbye now!")

def dream_master():
    """The Dream master"""
    this_actor.info("Let's create a lazy guy.")  # Create a lazy_guy process
    lazy = Actor.create("Lazy", this_actor.get_host(), lazy_guy)
    this_actor.info("Let's wait a little bit...")
    this_actor.sleep_for(10)  # Wait for 10 seconds
    this_actor.info("Let's wake the lazy guy up! >:) BOOOOOUUUHHH!!!!")
    if lazy.is_suspended():
        lazy.resume()  # Then wake up the lazy_guy
    else:
        this_actor.error(
            "I was thinking that the lazy guy would be suspended now")

    this_actor.sleep_for(5)  # Repeat two times:
    this_actor.info("Suspend the lazy guy while he's sleeping...")
    lazy.suspend()  # Suspend the lazy_guy while he's asleep
    this_actor.info("Let him finish his siesta.")
    this_actor.sleep_for(10)  # Wait for 10 seconds
    this_actor.info("Wake up, lazy guy!")
    lazy.resume()  # Then wake up the lazy_guy again

def __call__(self):
        workload = 100E6
        host = this_actor.get_host()

        nb = host.get_pstate_count()
        this_actor.info("Count of Processor states={:d}".format(nb))

        this_actor.info("Current power peak={:f}".format(host.speed))

        # Run a task
        this_actor.execute(workload)

        task_time = Engine.get_clock()
        this_actor.info("Task1 duration: {:.2f}".format(task_time))

        # Change power peak
        new_pstate = 2

        this_actor.info("Changing power peak value to {:f} (at index {:d})".format( host.get_pstate_speed(new_pstate), new_pstate))