diff --git a/compiler/base/hierarchy_layout.py b/compiler/base/hierarchy_layout.py
index 7fe838cb..c99b187e 100644
--- a/compiler/base/hierarchy_layout.py
+++ b/compiler/base/hierarchy_layout.py
@@ -13,6 +13,7 @@ from tech import drc, GDS
 from tech import layer as techlayer
 from tech import layer_indices
 from tech import layer_stacks
+from tech import preferred_directions
 import os
 from globals import OPTS
 from vector import vector
diff --git a/compiler/tests/06_hierarchical_predecode2x4_test.py b/compiler/tests/06_hierarchical_predecode2x4_test.py
index c2b51f10..a119c9d4 100755
--- a/compiler/tests/06_hierarchical_predecode2x4_test.py
+++ b/compiler/tests/06_hierarchical_predecode2x4_test.py
@@ -8,13 +8,14 @@
 #
 import unittest
 from testutils import *
-import sys,os
+import sys, os
 sys.path.append(os.getenv("OPENRAM_HOME"))
 import globals
 from globals import OPTS
 from sram_factory import factory
 import debug
 
+
 class hierarchical_predecode2x4_test(openram_test):
 
     def runTest(self):
diff --git a/compiler/tests/06_hierarchical_predecode3x8_test.py b/compiler/tests/06_hierarchical_predecode3x8_test.py
index c1471a40..8aa3e6ed 100755
--- a/compiler/tests/06_hierarchical_predecode3x8_test.py
+++ b/compiler/tests/06_hierarchical_predecode3x8_test.py
@@ -8,13 +8,14 @@
 #
 import unittest
 from testutils import *
-import sys,os
+import sys, os
 sys.path.append(os.getenv("OPENRAM_HOME"))
 import globals
 from globals import OPTS
 from sram_factory import factory
 import debug
 
+
 class hierarchical_predecode3x8_test(openram_test):
 
     def runTest(self):
diff --git a/compiler/tests/06_hierarchical_predecode4x16_test.py b/compiler/tests/06_hierarchical_predecode4x16_test.py
index 7ded6144..169579c8 100755
--- a/compiler/tests/06_hierarchical_predecode4x16_test.py
+++ b/compiler/tests/06_hierarchical_predecode4x16_test.py
@@ -16,7 +16,6 @@ from sram_factory import factory
 import debug
 
 
-# @unittest.skip("SKIPPING hierarchical_predecode4x16_test")
 class hierarchical_predecode4x16_test(openram_test):
 
     def runTest(self):