diff --git a/pyro/simulation_null.py b/pyro/simulation_null.py
index 771ad1b7b..0baaea658 100644
--- a/pyro/simulation_null.py
+++ b/pyro/simulation_null.py
@@ -1,8 +1,8 @@
 import h5py
+import numpy as np
 
 import pyro.mesh.boundary as bnd
 import pyro.util.profile_pyro as profile
-import numpy as np
 from pyro.mesh import patch
 from pyro.util import msg