From a7f967fb20742917bbd9dcd68fa66ae0fe0dd644 Mon Sep 17 00:00:00 2001
From: jfkirk <james.f.kirk@gmail.com>
Date: Tue, 14 Jul 2015 15:18:55 -0400
Subject: [PATCH] BUG: Replaces is-check against string

Replaces an " is 'None' " check with " != None "
---
 zipline/assets/assets.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/zipline/assets/assets.py b/zipline/assets/assets.py
index 23784343..02fe702e 100644
--- a/zipline/assets/assets.py
+++ b/zipline/assets/assets.py
@@ -877,7 +877,7 @@ class AssetFinder(object):
                 try:
                     row_value = row[field]
                     # Avoid passing placeholders
-                    if row_value and (row_value is not 'None'):
+                    if row_value and (row_value != 'None'):
                         metadata_dict[field] = row[field]
                 except KeyError:
                     continue