old_contents: #!/usr/bin/env python3
  import unittest
  
  if __name__ == '__main__':
      testsuite = unittest.TestLoader().discover('test')
      unittest.TextTestRunner(verbosity=1).run(testsuite)
  
new_contents: #!/usr/bin/env python3
  import unittest
  
  if __name__ == '__main__':
      testsuite = unittest.TestLoader().discover('tests')
      unittest.TextTestRunner(verbosity=1).run(testsuite)
  
subject: Change test directory to tests