python workaround gpiozero when_motion with multiple sensors

Question

i'm trying to listen on 3 motion sensors, each one triggering its own sound

i'm using when_motion because it's creating a thread, so i can do other thing while the sensors doing their thing

but!

you can assign a function to it as long as it has no parameter.

well, not what says the documentation:

"This can be set to a function which accepts no (mandatory) parameters, or a Python function which accepts a single mandatory parameter (with as many optional parameters as you like). If the function accepts a single mandatory parameter, the device that activated it will be passed as that parameter."

not sure of what it means because when i do that

MotionSensor(17).when_motion = myfunction(parameter)

i get this error:

/usr/lib/python3/dist-packages/gpiozero/mixins.py:191: CallbackSetToNone: The callback was set to None. This may have been unintentional e.g. btn.when_pressed = pressed() instead of btn.when_pressed = pressed
  warnings.warn(CallbackSetToNone(callback_warning))

while this works fine:

MotionSensor(17).when_motion = myfunction

so i'm trying to create a class to workaround that

but i don't know how to pass a variable (call element) from the class to the function without create a parameter for the function

how will you do that?

my non working code so far:

from gpiozero import MotionSensor
import vlc
from time import sleep

player = vlc.MediaPlayer()
state = 0

class PIR:
    def __init__(self, pin, element):
        self.pir = MotionSensor(pin=pin)
        self.pir.when_motion = self.motion
        self.element = element

    def motion(self):
        if state == 0:
            print ("{}!".format(element))
            player.set_media(vlc.Media("{}.wav".format(element)))
            player.play()


Pir1 = PIR(17,"feu")
Pir2 = PIR(22,"eau")
Pir3 = PIR(27,"vent")

while True:
    print("listening")
    sleep(1)