two pdb imports is redundant

you import pdb twice.. also restructured the whitespace to reflect trainval_net.py

test_net.py

@@ -15,7 +15,9 @@
 import pprint
 import pdb
 import time
+
 import cv2
+
 import torch
 from torch.autograd import Variable
 import torch.nn as nn
@@ -28,11 +30,10 @@
 from model.nms.nms_wrapper import nms
 from model.rpn.bbox_transform import bbox_transform_inv
 from model.utils.net_utils import save_net, load_net, vis_detections
+
 from model.faster_rcnn.vgg16 import vgg16
 from model.faster_rcnn.resnet import resnet
 
-import pdb
-
 try:
     xrange          # Python 2
 except NameError: