from machine import Pin
import utime

gpio_18 = Pin(18,Pin.OUT)
gpio_19 = Pin(19,Pin.OUT)

while True:
    gpio_18.value(1)
    gpio_19.value(0)
    utime.sleep(1)
    gpio_18.value(0)
    gpio_19.value(1)
    utime.sleep(0.5)
    
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