Fix typo

theano/scan_module/scan_opt.py

@@ -616,7 +616,7 @@ class PushOutScanOutput(gof.Optimizer):
         # impossible to know for how many steps it will run.
         nodelist = [x for x in fgraph.toposort()
                     if (isinstance(x.op, scan_op.Scan) and
-                        not x.op.as_while]
+                        not x.op.as_while)]
         for node in nodelist:
             # Process the node as long as something gets optimized
             while node != None: