old_contents: from mpi4py_test import MPITester
  import sys
  import os.path
  
  tester = MPITester(os.path.abspath(__file__), "mpsort")
  
  tester.main(sys.argv)
  
new_contents: from mpi4py_test import MPITester
  import sys
  import os.path
  
  tester = MPITester(os.path.abspath(__file__), "mpsort")
  
  tester.main(sys.argv[1:])
  
subject: fix tests.