old_contents: #!/usr/bin/env python 
  
  import sys 
  
  
  def osCheck(): 
      """ Check if system is running 'Linux' """
      if not sys.platform.startswith('linux'): 
          print 'Sorry, we can\'t continue. Ciao' 
          exit()
  
  osCheck()
  
  
  
new_contents: #!/usr/bin/env python 
  
  import sys 
  
  
  def osCheck(): 
      """ Check if system is running 'Linux' """
      if not sys.platform.startswith('linux'): 
          print 'Sorry, we can\'t continue. Ciao' 
          sys.exit()
  
  osCheck()
  
  
  
subject: change to sys.exit()