From af70652321c64a743b856f8f5e7da2cc2ee8198b 2016-05-05 22:45:36
From: Matthias Bussonnier <bussonniermatthias@gmail.com>
Date: 2016-05-05 22:45:36
Subject: [PATCH] Require recent enough traitlets

so we can start to force the new `.tag()` syntax.

---

diff --git a/setup.py b/setup.py
index 8902e8a..b0c0151 100755
--- a/setup.py
+++ b/setup.py
@@ -195,7 +195,7 @@ install_requires = [
     'decorator',
     'pickleshare',
     'simplegeneric>0.8',
-    'traitlets',
+    'traitlets>=4.2',
     'prompt_toolkit>=1.0.0,<2.0.0',
     'pygments',
 ]