new_contents: import unittest
  from pathlib import Path
  import unittest
  import cryptol
  from cryptol.cryptoltypes import CryptolApplication, CryptolLiteral
  from cryptol.bitvector import BV
  
  
  class TestEvenMansour(unittest.TestCase):
      def test_EvenMansour(self):
          c = cryptol.connect()
          c.load_file(str(Path('tests','cryptol','test-files','examples','contrib','EvenMansour.cry')))
                  
          F_10_4 = c.eval('F:[10][4]').result()
          self.assertTrue(c.call('is_a_permutation', F_10_4).result())
          
          Finv_10_4 = c.eval("F':[10][4]").result()
          digits = [ BV(size=4, value=i) for i in range(0,10) ]
                   # ^ the same as: c.eval('[0..9]:[_][4]').result()
          self.assertTrue(c.call('is_inverse_permutation', digits, F_10_4, Finv_10_4).result())
          
          self.assertTrue(c.check('E_and_D_are_inverses').result().success)
          
  
  if __name__ == "__main__":
      unittest.main()
  
subject: add test_EvenMansour