From 9bdc2c87349305ba6c6670b8b7914d4bf996f46c Mon Sep 17 00:00:00 2001
From: Thomas Wiecki <thomas.wiecki@gmail.com>
Date: Tue, 3 Feb 2015 11:36:00 +0100
Subject: [PATCH] BUG: Support algo_filename being None. Fixes #480.

---
 zipline/algorithm.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/zipline/algorithm.py b/zipline/algorithm.py
index df29f5c9..b3d7097e 100644
--- a/zipline/algorithm.py
+++ b/zipline/algorithm.py
@@ -201,7 +201,9 @@ class TradingAlgorithm(object):
         self.event_manager = EventManager()
 
         if self.algoscript is not None:
-            filename = kwargs.pop('algo_filename', '<string>')
+            filename = kwargs.pop('algo_filename')
+            if filename is None:
+                filename = '<string>'
             code = compile(self.algoscript, filename, 'exec')
             exec_(code, self.namespace)
             self._initialize = self.namespace.get('initialize')