diff --git a/test/crossrunner/util.py b/test/crossrunner/util.py
index 750ed47..e2d195a 100644
--- a/test/crossrunner/util.py
+++ b/test/crossrunner/util.py
@@ -21,11 +21,11 @@
 
 
 def merge_dict(base, update):
-  """Update dict concatenating list values"""
-  res = copy.deepcopy(base)
-  for k, v in list(update.items()):
-    if k in list(res.keys()) and isinstance(v, list):
-      res[k].extend(v)
-    else:
-      res[k] = v
-  return res
+    """Update dict concatenating list values"""
+    res = copy.deepcopy(base)
+    for k, v in list(update.items()):
+        if k in list(res.keys()) and isinstance(v, list):
+            res[k].extend(v)
+        else:
+            res[k] = v
+    return res