print("Sin error")
from time import sleep_ms
from machine import Pin,PWM
#clase PWM(pin,Frec) sintaxis 
pwn=PWM(Pin(2),1000)
def metodopwm():
  try:
    while True:
      for i in range (0,90):
        pwm.duty(i)
        sleep_ms(10)
      for i in range (0,90):
        pwm.duty(90-i)
        sleep_ms(10)
  except:
    pass
  while True:
    metodopwm()