Python 2/3 compatibility issues that were not resolved in the latest commit.

test/test_api/test_api.py

@@ -131,4 +131,4 @@ def test_goto_definition_not_multiple():
 
 def test_usage_description():
     descs = [u.description for u in api.Script("foo = ''; foo").usages()]
-    assert set(descs) == {"foo = ''", 'foo'}
+    assert set(descs) == set(["foo = ''", 'foo'])

test/test_api/test_full_name.py

@@ -44,7 +44,7 @@ class MixinTestFullName(object):
 class TestFullNameWithGotoDefinitions(MixinTestFullName, TestCase):
     operation = 'goto_definitions'
 
-    @pytest.mark.skipif('sys.version_info[:2] <= (2, 6)', reason='Python 2.6 also yields None.')
+    @pytest.mark.skipif('sys.version_info[0] < 3', reason='Python 2 also yields None.')
     def test_tuple_mapping(self):
         self.check("""
         import re

test/test_evaluate/test_helpers.py

@@ -1,3 +1,5 @@
+from jedi._compatibility import unicode
+
 from jedi.evaluate import helpers
 from jedi.parser import representation as pr
 from jedi.parser import Parser