new_contents: import time
  import RPi.GPIO as GPIO
  GPIO.setmode(GPIO.BOARD)
  GPIO.setup(15, GPIO.OUT)
  
  p = GPIO.PWM(15, 50)
  p.start(0)
  try:
      while 1:
          for dc in range(0, 101, 5):
              p.ChangeDutyCycle(dc)
              time.sleep(0.1)
          for dc in range(100, -1, -5):
              p.ChangeDutyCycle(dc)
              time.sleep(0.1)
  except KeyboardInterrupt:
      pass
  p.stop()
  GPIO.cleanup()
subject: Add pwm file