Fix another filter() use in scan for python3

theano/scan_module/scan.py

@@ -785,8 +785,7 @@ def scan(fn,
                    not isinstance(x, SharedVariable) and
                    not isinstance(x, gof.Constant)),
         gof.graph.inputs(fake_outputs))
-    extra_inputs = filter(lambda x: x not in args + fake_nonseqs,
-                                    all_inputs)
+    extra_inputs = [x for x in all_inputs if x not in args + fake_nonseqs]
     non_seqs += extra_inputs
     ## Note we do not use all_inputs directly since the order of variables
     ## in args is quite important