new_contents: import unittest
  
  from openid import codecutil  # registers encoder
  
  
  class EncoderTest(unittest.TestCase):
      def test_handler_registered(self):
          self.assertEqual(
              "foo".encode('ascii', errors='oid_percent_escape'),
              b"foo")
  
      def test_encoding(self):
          s = 'l\xa1m\U00101010n'
          expected = b'l%C2%A1m%F4%81%80%90n'
          self.assertEqual(
              s.encode('ascii', errors='oid_percent_escape'),
              expected)
  
  
  if __name__ == '__main__':
      unittest.main()
  
subject: Add tests for new codecutil module -- very basic for now