from machine import Pin
import time

mq135_do = Pin(25, Pin.IN)
buzzer = Pin(26,Pin.OUT)

print("MQ-135 warming up...")
time.sleep(20)

while True:
    gas_detected = gas_pin.value()
    if gas_detected == 0:
        print("Poor Air Quality Detected")
        buzzer.on()
    else:
        print("Air Quality Normal")
        buzzer.off()

    time.sleep(1)