old_contents: from __future__ import absolute_import
  from __future__ import print_function
  from __future__ import division
  
  
  def quick_sort(a_list):
      """Quick sort algortihm with list comprehension recursion."""
      if len(a_list) <= 1:
          return a_list
      pivot_value = a_list[len(a_list) // 2]
      left_list = [x for x in a_list if x < pivot_value]
      middle_list = [x for x in a_list if x == pivot_value]
      right_list = [x for x in a_list if x > pivot_value]
      return quick_sort(left_list) + middle_list + quick_sort(right_list)
  
  
  def main():
      a_list = [54, 26, 93, 17, 77, 31, 44, 55, 20]
      print('a_list: \n'.format(a_list))
      print('Quick sort with list comprehension: ')
      print(quick_sort(a_list))
  
  
  if __name__ == '__main__':
      main()
  
new_contents: from __future__ import absolute_import
  from __future__ import print_function
  from __future__ import division
  
  
  def quick_sort(a_list):
      """Quick sort algortihm with list comprehension recursion."""
      if len(a_list) <= 1:
          return a_list
      pivot_value = a_list[len(a_list) // 2]
      left_list = [x for x in a_list if x < pivot_value]
      middle_list = [x for x in a_list if x == pivot_value]
      right_list = [x for x in a_list if x > pivot_value]
      return quick_sort(left_list) + middle_list + quick_sort(right_list)
  
  
  def main():
      a_list = [54, 26, 93, 17, 77, 31, 44, 55, 20]
      print('a_list: {}'.format(a_list))
      print('Quick sort with list comprehension: ')
      print(quick_sort(a_list))
  
  
  if __name__ == '__main__':
      main()
  
subject: Revise printing list