From 8e32d493480d7783fcbeb491284fde4bae2d09e4 Mon Sep 17 00:00:00 2001
From: Scott Sanderson <ssanderson@quantopian.com>
Date: Fri, 13 May 2016 19:47:15 -0400
Subject: [PATCH] MAINT: Just use a genexpr instead of map(partial).

---
 zipline/pipeline/factors/factor.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/zipline/pipeline/factors/factor.py b/zipline/pipeline/factors/factor.py
index b14a4a0f..85ccb1e6 100644
--- a/zipline/pipeline/factors/factor.py
+++ b/zipline/pipeline/factors/factor.py
@@ -1,7 +1,7 @@
 """
 factor.py
 """
-from functools import partial, wraps
+from functools import wraps
 from operator import attrgetter
 from numbers import Number
 
@@ -1224,8 +1224,7 @@ class CustomFactor(PositiveWindowLengthMixin, CustomTermMixin, Factor):
                     factor=type(self).__name__,
                 )
             )
-        RecarrayField_ = partial(RecarrayField, self)
-        return iter(map(RecarrayField_, self.outputs))
+        return (RecarrayField(self, attr) for attr in self.outputs)
 
 
 class RecarrayField(SingleInputMixin, Factor):