Define unicode as str if using Python 3

The unicode object was renamed to str in Python 3

Change-Id: I1e4972fb07b313d3462587b3059bb3638d779625
diff --git a/subcmds/upload.py b/subcmds/upload.py
index e2fa261..0ee36df 100644
--- a/subcmds/upload.py
+++ b/subcmds/upload.py
@@ -25,10 +25,12 @@
 from project import RepoHook
 
 from pyversion import is_python3
+# pylint:disable=W0622
 if not is_python3():
-  # pylint:disable=W0622
   input = raw_input
-  # pylint:enable=W0622
+else:
+  unicode = str
+# pylint:enable=W0622
 
 UNUSUAL_COMMIT_THRESHOLD = 5