old_contents: #!/usr/bin/python3
  """
  TODO: DocString
  """
  
  
  def main():
      """
      main function
      """
      pass
  
  
  if __name__ == '__main__':
      main()
  
new_contents: #!/usr/bin/env python3
  """
  TODO: DocString
  """
  
  
  def main():
      """
      main function
      """
      pass
  
  
  if __name__ == '__main__':
      main()
  
subject: update python3 template