old_contents: #!/usr/bin/env python3
  
  import argparse
  import random
  import sys
  
  DESCRIPTION = '''Shuffle the arguments received, if called without arguments
                   the lines read from stdin will be shuffled and printed to
                   stdout'''
  
  
  def get_list():
      return sys.stdin.readlines()
  
  
  def print_list(list_):
      for elem in list_:
          print(elem.rstrip())
  
  
  def main():
      parser = argparse.ArgumentParser(description=DESCRIPTION)
      (args, list_) = parser.parse_known_args()
      r = random.SystemRandom()
      if not list_:
          list_ = get_list()
      r.shuffle(list_)
      print_list(list_)
  
  
  if __name__ == '__main__':
      main()
  
new_contents: #!/usr/bin/env python3
  
  import argparse
  import random
  import sys
  
  DESCRIPTION = '''Shuffle the arguments received, if called without arguments
                   the lines read from stdin will be shuffled and printed to
                   stdout'''
  
  
  def get_list():
      return sys.stdin.readlines()
  
  
  def print_list(list_):
      for elem in list_:
          print(elem.rstrip())
  
  
  def main():
      parser = argparse.ArgumentParser(description=DESCRIPTION)
      (_, list_) = parser.parse_known_args()
      r = random.SystemRandom()
      if not list_:
          list_ = get_list()
      r.shuffle(list_)
      print_list(list_)
  
  
  if __name__ == '__main__':
      main()
  
subject: Remove unused variable args