Small doc change and formatting

letsencrypt/acme/challenges.py

@@ -184,7 +184,8 @@ class ProofOfPossession(ClientChallenge):
         """Hints for "proofOfPossession" challenge.
 
         :ivar jwk: JSON Web Key (:class:`letsencrypt.acme.jose.JWK`)
-        :ivar list certs: List of :class:`M2Crypto.X509.X509` certificates.
+        :ivar list certs: List of :class:`letsencrypt.acme.jose.ComparableX509`
+            certificates.
 
         """
         jwk = jose.Field("jwk", decoder=jose.JWK.from_json)

letsencrypt/client/tests/auth_handler_test.py

@@ -581,8 +581,7 @@ class GenChallengePathTest(unittest.TestCase):
         combos = ((0, 1),)
 
         self.assertRaises(errors.LetsEncryptAuthHandlerError,
-                          self._call,
-                          challs, prefs, combos)
+                          self._call, challs, prefs, combos)
 
 
 class MutuallyExclusiveTest(unittest.TestCase):