commit ae1618ec6ab66beef49c3d27ac0083c4115bd8cb
Author: Jeremy Katz <katzj@redhat.com>
Date:   Wed Sep 12 10:40:12 2007 -0400

    allow passing in an already created display object

diff --git a/yum/rpmtrans.py b/yum/rpmtrans.py
index ecddce1..f77400e 100644
--- a/yum/rpmtrans.py
+++ b/yum/rpmtrans.py
@@ -115,7 +115,10 @@ class SimpleCliCallBack(RPMBaseCallback):
 
 class RPMTransaction:
     def __init__(self, base, test=False, display=NoOutputCallBack):
-        self.display = display() # display callback
+        if not callable(display):
+            self.display = display
+        else:
+            self.display = display() # display callback
         self.base = base # base yum object b/c we need so much
         self.test = test # are we a test?