from machine import Pin
from time import sleep

sleep(0.1) # Wait for USB to become ready
led_pin = 16

led = Pin(led_pin, Pin.OUT)
led.off()
atraso = 0.5

while True:
  led.on()
  sleep(atraso)
  led.off()
  sleep(atraso)

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BOOTSELLED1239USBRaspberryPiPico©2020RP2-8020/21P64M15.00TTT