Change test to be compatible with Python 2.7

Author: normpad

test/commands/extended/replay_bundle_test.py

@@ -596,16 +596,15 @@ def test_happy_path(self):
       'trytes': bundle.as_tryte_strings(),
     }
 
-    def mock_send_trytes(self,request):
+    def mock_send_trytes(_,request):
       """
       Ensures that the correct trytes are sent to the ``sendTrytes`` command
       to replay the bundle.
 
       References:
         - https://github.com/iotaledger/iota.lib.py/issues/74
       """
-      from unittest import TestCase
-      TestCase().assertEqual(request['trytes'], send_trytes_response['trytes'])
+      self.assertEqual(request['trytes'], send_trytes_response['trytes'])
       return send_trytes_response
 
     with mock.patch(