diff --git a/detectron/ops/zero_even_op.cu b/detectron/ops/zero_even_op.cu
index a606727d9..c2e5b833f 100644
--- a/detectron/ops/zero_even_op.cu
+++ b/detectron/ops/zero_even_op.cu
@@ -35,7 +35,7 @@ template <>
 bool ZeroEvenOp<float, CUDAContext>::RunOnDevice() {
   // Retrieve the input tensor.
   const auto& X = Input(0);
-  CAFFE_ENFORCE(X.ndim() == 1);
+  CAFFE_ENFORCE(X.dim() == 1);
 
   // Initialize the output tensor to a copy of the input tensor.
   auto* Y = Output(0);
diff --git a/detectron/roi_data/fast_rcnn.py b/detectron/roi_data/fast_rcnn.py
index 56e96987b..a9f4cb381 100644
--- a/detectron/roi_data/fast_rcnn.py
+++ b/detectron/roi_data/fast_rcnn.py
@@ -47,7 +47,6 @@ def get_fast_rcnn_blob_names(is_training=True):
         # labels_int32 blob: R categorical labels in [0, ..., K] for K
         # foreground classes plus background
         blob_names += ['labels_int32']
-    if is_training:
         # bbox_targets blob: R bounding-box regression targets with 4
         # targets per class
         blob_names += ['bbox_targets']
@@ -157,7 +156,7 @@ def _sample_rois(roidb, im_scale, batch_idx):
     # against there being fewer than desired)
     bg_rois_per_this_image = rois_per_image - fg_rois_per_this_image
     bg_rois_per_this_image = np.minimum(bg_rois_per_this_image, bg_inds.size)
-    # Sample foreground regions without replacement
+    # Sample background regions without replacement
     if bg_inds.size > 0:
         bg_inds = npr.choice(
             bg_inds, size=bg_rois_per_this_image, replace=False
diff --git a/detectron/tests/test_zero_even_op.py b/detectron/tests/test_zero_even_op.py
index 82076a8a9..bd2ca4526 100644
--- a/detectron/tests/test_zero_even_op.py
+++ b/detectron/tests/test_zero_even_op.py
@@ -47,7 +47,7 @@ def _run_zero_even_op_gpu(self, X):
 
     def test_throws_on_non_1D_arrays(self):
         X = np.zeros((2, 2), dtype=np.float32)
-        with self.assertRaisesRegexp(RuntimeError, 'X\.ndim\(\) == 1'):
+        with self.assertRaisesRegexp(RuntimeError, 'X\.dim\(\) == 1'):
             self._run_zero_even_op(X)
 
     def test_handles_empty_arrays(self):
@@ -84,7 +84,7 @@ def test_handles_odd_length_arrays(self):
 
     def test_gpu_throws_on_non_1D_arrays(self):
         X = np.zeros((2, 2), dtype=np.float32)
-        with self.assertRaisesRegexp(RuntimeError, 'X\.ndim\(\) == 1'):
+        with self.assertRaisesRegexp(RuntimeError, 'X\.dim\(\) == 1'):
             self._run_zero_even_op_gpu(X)
 
     def test_gpu_handles_empty_arrays(self):
diff --git a/detectron/utils/io.py b/detectron/utils/io.py
index 4501b0a3f..946bd6d6d 100644
--- a/detectron/utils/io.py
+++ b/detectron/utils/io.py
@@ -39,11 +39,11 @@
 def save_object(obj, file_name, pickle_format=2):
     """Save a Python object by pickling it.
 
-Unless specifically overridden, we want to save it in Pickle format=2 since this
-will allow other Python2 executables to load the resulting Pickle. When we want
-to completely remove Python2 backward-compatibility, we can bump it up to 3. We
-should never use pickle.HIGHEST_PROTOCOL as far as possible if the resulting
-file is manifested or used, external to the system.
+    Unless specifically overridden, we want to save it in Pickle format=2 since this
+    will allow other Python2 executables to load the resulting Pickle. When we want
+    to completely remove Python2 backward-compatibility, we can bump it up to 3. We
+    should never use pickle.HIGHEST_PROTOCOL as far as possible if the resulting
+    file is manifested or used, external to the system.
     """
     file_name = os.path.abspath(file_name)
     # Avoid filesystem race conditions (particularly on network filesystems)