old_contents: import time
  import RPi.GPIO as GPIO
  
  
  # use Broadcom pin numbers
  GPIO.setmode(GPIO.BCM)
  
  BUTTON_PIN = 4
  
  GPIO.setup(BUTTON_PIN, GPIO.IN)
  
  while True:
    # print bin state
    print GPIO.input(BUTTON_PIN)
    time.sleep(1)
  
  GPIO.cleanup()
  
new_contents: import time
  import RPi.GPIO as GPIO
  
  
  # use Broadcom pin numbers
  GPIO.setmode(GPIO.BCM)
  
  BUTTON_PIN = 4
  
  GPIO.setup(BUTTON_PIN, GPIO.IN)
  
  while True:
    # print pin state
    print GPIO.input(BUTTON_PIN)
    time.sleep(1)
  
  GPIO.cleanup()
  
subject: Fix typo