old_contents: from __future__ import absolute_import, print_function
  import os
  import unittest
  
  DATA_DIR = os.path.dirname(os.path.abspath(__file__))
  print('looking for data in "{}"'.format(DATA_DIR))
  
new_contents: from __future__ import absolute_import, print_function
  import os
  
  DATA_DIR = os.path.dirname(os.path.abspath(__file__))
  print('looking for data in "{}"'.format(DATA_DIR))
  
subject: Remove unused import