[Tutor] Python GPIO Code Help Needed

[Bill Bright]

Thanks to everyone for the help. The code below seems to work. My question is why does oldstates need to multiplied by 32? Does this mean that the code will only work for 32 switches before I have to reset the Pi?

Code:
#!/usr/bin/env python

from time import sleep
import os
import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM)
GPIO.setup(23, GPIO.IN)
GPIO.setup(24, GPIO.IN)
GPIO.setup(25, GPIO.IN)
oldstates=[True]*32

def changed(channel):
        newstate = GPIO.input(channel)
        change = oldstates[channel] and not newstate
        oldstates[channel] = newstate
        return change

while True:
        if changed(23):
                os.system('mpg321 -g 95 a.mp3')
        if changed(24):
                os.system('mpg321 -g 95 b.mp3')
        if changed(25):
                os.system('mpg321 -g 95 c.mp3')
        sleep(1.1);
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