new_contents: from __future__ import print_function
  from __future__ import division
  
  
  def merge_sort(a_list):
      """Merge sort algortihm."""
      pass
  
  
  def main():
      a_list = [54, 26, 93, 17, 77, 31, 44, 55, 20]
      print('a_list: \n{}'.format(a_list))
      print('By Merge Sort: ')
      merge_sort(a_list)
  
  
  if __name__ == '__main__':
      main()
  
subject: Add merge_sort.py