Hello Raspberry Pi

The example show how to detect events of GPIO, to detect button pressed/released. It have the same operation in the post "Python RPi.GPIO: Button and LED".

import RPi.GPIO as GPIO
import time
GPIO.setmode(GPIO.BCM)
# pin 17 as input with pull-up resistor
GPIO.setup(17, GPIO.IN, pull_up_down=GPIO.PUD_UP)
# pin 18 as output
GPIO.setup(18, GPIO.OUT)
def ButtonCallback(channel):
 if (GPIO.input(17)):
 GPIO.output(18, False)
 else:
 GPIO.output(18, True)
 
GPIO.add_event_detect(17, GPIO.BOTH, callback=ButtonCallback);
while(True):
 #do nothing
 time.sleep(1)