-
Notifications
You must be signed in to change notification settings - Fork 0
/
test_time_defense.py
534 lines (452 loc) · 20.4 KB
/
test_time_defense.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
'''
'''
from PIL import Image
import random
import torch
import torch.nn as nn
import torch.optim as optim
import numpy as np
from torchvision import datasets, models, transforms
import time
import os
import copy
import logging
import sys
import configparser
import glob
from tqdm import tqdm
from dataset import LabeledDataset
from timm.models.vision_transformer import VisionTransformer, _cfg, vit_large_patch16_224
import pdb
from functools import partial
from vit_grad_rollout import *
import cv2
import torch.nn.functional as F
config = configparser.ConfigParser()
config.read(sys.argv[1])
experimentID = config["experiment"]["ID"]
options = config["finetune"]
clean_data_root = options["clean_data_root"]
poison_root = options["poison_root"]
gpu = int(options["gpu"])
epochs = int(options["epochs"])
patch_size = int(options["patch_size"])
eps = int(options["eps"])
rand_loc = options.getboolean("rand_loc")
trigger_id = int(options["trigger_id"])
num_poison = int(options["num_poison"])
num_classes = int(options["num_classes"])
batch_size = 50
logfile = options["logfile"].format(experimentID, rand_loc, eps, patch_size, num_poison, trigger_id)
lr = float(options["lr"])
momentum = float(options["momentum"])
options = config["poison_generation"]
target_wnid = options["target_wnid"]
source_wnid_list = options["source_wnid_list"].format(experimentID)
save=True
with open(source_wnid_list) as f2:
source_wnids = f2.readlines()
source_wnids = [s.strip() for s in source_wnids]
source_wnid = source_wnids[0]
num_source = int(options["num_source"])
edge_length = 30 #default - 30
block =False
checkpointDir = "checkpoints/" + experimentID + "/rand_loc_" + str(rand_loc) + "/eps_" + str(eps) + \
"/patch_size_" + str(patch_size) + "/num_poison_" + str(num_poison) + "/trigger_" + str(trigger_id)
save_path = experimentID + "/rand_loc_" + str(rand_loc) + "/eps_" + str(eps) + \
"/patch_size_" + str(patch_size) + "/num_poison_" + str(num_poison) + "/trigger_" + str(trigger_id)
#
if not os.path.exists(os.path.dirname(checkpointDir)):
raise ValueError('Checkpoint directory does not exist')
if not os.path.exists(save_path):
os.makedirs(save_path)
os.makedirs(os.path.join(save_path,'patched'))
os.makedirs(os.path.join(save_path,'patched_top'))
os.makedirs(os.path.join(save_path,'orig_image'))
os.makedirs(os.path.join(save_path,'patched_blocked'))
# create heatmap from mask on image
def show_cam_on_image(img, mask):
heatmap = cv2.applyColorMap(np.uint8(255 * mask), cv2.COLORMAP_JET)
heatmap = np.float32(heatmap) / 255
cam = heatmap + np.float32(img)
cam = cam / np.max(cam)
return np.uint8(255 * cam)
model_name = 'deit_base_patch16_224'
# Flag for feature extracting. When False, we finetune the whole model,
# when True we only update the reshaped layer params
feature_extract = True
class_dir_list = sorted(os.listdir('/datasets/imagenet/train'))
trans_trigger = transforms.Compose([transforms.Resize((patch_size, patch_size)),
transforms.ToTensor(),
transforms.Normalize(mean=[0.485, 0.456, 0.406],std=[0.229, 0.224, 0.225])
])
trigger = Image.open('data/triggers/trigger_{}.png'.format(trigger_id)).convert('RGB')
trigger = trans_trigger(trigger).unsqueeze(0).cuda(gpu)
def train_model(model, dataloaders, criterion, optimizer, num_epochs=25, is_inception=False):
assert optimizer is None,'Optimizer is not None, Training might occur'
since = time.time()
best_model_wts = copy.deepcopy(model.state_dict())
best_acc = 0.0
test_acc_arr = np.zeros(num_epochs)
zoomed_test_acc_arr = np.zeros(num_epochs)
patched_acc_arr = np.zeros(num_epochs)
notpatched_acc_arr = np.zeros(num_epochs)
for epoch in range(1):
print('Epoch:1')
for phase in ['patched']:
top_all_CH = list()
target_all_CH = list()
pos_x = list()
pos_y = list()
# save patch location
patch_loc = list()
target_IoU = list()
top_IoU = list()
target_success_IoU = list()
if phase == 'train':
assert False,'Model in Training mode'
else:
model.eval() # Set model to evaluate mode
running_loss = 0.0
running_corrects = 0
running_source_corrects = 0
zoomed_asr = 0
zoomed_source_acc = 0
zoomed_acc = 0
# Set nn in patched phase to be higher if you want to cover variability in trigger placement
if phase == 'patched':
nn=1
else:
nn=1
for ctr in range(0, nn):
# Iterate over data.
debug_idx= 0
for inputs, labels,paths in tqdm(dataloaders[phase]):
debug_idx+=1
inputs = inputs.cuda(gpu)
labels = labels.cuda(gpu)
source_labels = class_dir_list.index(source_wnid)*torch.ones_like(labels).cuda(gpu)
notpatched_inputs = inputs.clone()
if phase == 'patched':
random.seed(1)
for z in range(inputs.size(0)):
if not rand_loc:
start_x = inputs.size(3)-patch_size-5
start_y = inputs.size(3)-patch_size-5
else:
start_x = random.randint(0, inputs.size(3)-patch_size-1)
start_y = random.randint(0, inputs.size(3)-patch_size-1)
pos_y.append(start_y)
pos_x.append(start_x)
# patch_loc.append((start_x, start_y))
inputs[z, :, start_y:start_y+patch_size, start_x:start_x+patch_size] = trigger#
if True:
if is_inception and phase == 'train':
# From https://discuss.pytorch.org/t/how-to-optimize-inception-model-with-auxiliary-classifiers/7958
outputs, aux_outputs = model(inputs)
loss1 = criterion(outputs, labels)
loss2 = criterion(aux_outputs, labels)
loss = loss1 + 0.4*loss2
else:
with torch.no_grad():
outputs = model(inputs)
loss = criterion(outputs, labels)
_, preds = torch.max(outputs, 1)
zoomed_outputs = torch.zeros(outputs.shape).cuda()
if (phase == 'patched' or phase =='notpatched' or phase =='test') :
for b1 in range(inputs.shape[0]):
class_idx = outputs[b1].unsqueeze(0).data.topk(1, dim=1)[1][0].tolist()[0]
attention_rollout = VITAttentionGradRollout(model,
discard_ratio=0.9)
top_mask = attention_rollout(inputs[b1].unsqueeze(0).cuda(),category_index = class_idx)
attention_rollout.clear_cache()
attention_rollout.attentions = []
attention_rollout.attention_gradients = []
# target_mask = attention_rollout(inputs[b1].unsqueeze(0).cuda(),category_index = labels[b1].item())
np_img = invTrans(inputs[b1]).permute(1, 2, 0).data.cpu().numpy()
notpatched_np_img = invTrans(notpatched_inputs[b1]).permute(1, 2, 0).data.cpu().numpy()
top_mask = cv2.resize(top_mask, (np_img.shape[1], np_img.shape[0]))
# target_mask = cv2.resize(target_mask, (np_img.shape[1], np_img.shape[0]))
filter = torch.ones((edge_length+1, edge_length+1))
filter = filter.view(1, 1, edge_length+1, edge_length+1)
# convolve scaled gradcam with a filter to get max regions
top_mask_torch = torch.from_numpy(top_mask)
top_mask_torch = top_mask_torch.unsqueeze(0).unsqueeze(0)
top_mask_conv = F.conv2d(input=top_mask_torch,
weight=filter, padding=patch_size//2)
# top_mask_conv = top_mask_torch.clone()
top_mask_conv = top_mask_conv.squeeze()
top_mask_conv = top_mask_conv.numpy()
top_max_cam_ind = np.unravel_index(np.argmax(top_mask_conv), top_mask_conv.shape)
top_y = top_max_cam_ind[0]
top_x = top_max_cam_ind[1]
# alternate way to choose small region which ensures args.edge_length x args.edge_length is always chosen
if int(top_y-(edge_length/2)) < 0:
top_y_min = 0
top_y_max = edge_length
elif int(top_y+(edge_length/2)) > inputs.size(2):
top_y_max = inputs.size(2)
top_y_min = inputs.size(2) - edge_length
else:
top_y_min = int(top_y-(edge_length/2))
top_y_max = int(top_y+(edge_length/2))
if int(top_x-(edge_length/2)) < 0:
top_x_min = 0
top_x_max = edge_length
elif int(top_x+(edge_length/2)) > inputs.size(3):
top_x_max = inputs.size(3)
top_x_min = inputs.size(3) - edge_length
else:
top_x_min = int(top_x-(edge_length/2))
top_x_max = int(top_x+(edge_length/2))
# BLOCK - with black patch
zoomed_input = invTrans(copy.deepcopy(inputs[b1]))
if phase == 'patched':
zoomed_input[:, top_y_min:top_y_max, top_x_min:top_x_max] = 0*torch.ones(3, top_y_max-top_y_min, top_x_max-top_x_min)
zoom_path = os.path.join(save_path,'patched_blocked','image_'+str(batch_size*(debug_idx-1) +b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'.png')
else:
zoomed_input[:, top_y_min:top_y_max, top_x_min:top_x_max] = 0*torch.ones(3, top_y_max-top_y_min, top_x_max-top_x_min)
zoom_path = os.path.join(save_path,'notpatched_blocked','image_'+str(batch_size*(debug_idx-1) +b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'.png')
if save:
cv2.imwrite(zoom_path,np.uint8(255 * zoomed_input.permute(1, 2, 0).data.cpu().numpy()[:, :, ::-1]))
with torch.no_grad():
zoomed_outputs[b1] = model(normalize_fn(zoomed_input.unsqueeze(0).cuda()))[0]
torch.cuda.empty_cache()
if phase == 'patched':
top_mask = show_cam_on_image(np_img, top_mask)
top_im_path = os.path.join(save_path,'patched_top','image_'+str(b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'_attn.png')
patched_path = os.path.join(save_path,'patched','image_'+str(b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'.png')
orig_path = os.path.join(save_path,'orig_image','image_'+str(b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'.png')
if save:
cv2.imwrite(top_im_path, top_mask)
cv2.imwrite(patched_path, np.uint8(255 * np_img[:, :, ::-1]))
cv2.imwrite(orig_path, np.uint8(255 * notpatched_np_img[:, :, ::-1]))
else:
im_path = os.path.join(save_path,'notpatched_top','image_'+str(b1)+'_target_'+str(labels[b1].item())+'_top_pred_'+str(class_idx)+'_attn.png')
if save:
cv2.imwrite(im_path, top_mask)
_, zoomed_preds = torch.max(zoomed_outputs, 1)
# statistics
running_loss += loss.item() * inputs.size(0)
running_corrects += torch.sum(preds == labels.data)
running_source_corrects += torch.sum(preds == source_labels.data)
zoomed_asr += torch.sum(zoomed_preds == labels.data)
zoomed_source_acc += torch.sum(zoomed_preds == source_labels.data)
epoch_loss = running_loss / len(dataloaders[phase].dataset) / nn
epoch_acc = running_corrects.double() / len(dataloaders[phase].dataset) / nn
epoch_source_acc = running_source_corrects.double() / len(dataloaders[phase].dataset) / nn
zoomed_source_acc = zoomed_source_acc.double() / len(dataloaders[phase].dataset) / nn
zoomed_target_acc = zoomed_asr.double() / len(dataloaders[phase].dataset) / nn
zoomed_acc = zoomed_asr.double() / len(dataloaders[phase].dataset) / nn
print('{} Loss: {:.4f} Acc: {:.4f}'.format(phase, epoch_loss, epoch_acc))
if phase == 'test':
print("\nVal_acc {:3f}".format(epoch_acc* 100))
print("\nblocked_Val_acc {:3f}".format(zoomed_acc* 100))
test_acc_arr[epoch] = epoch_acc
zoomed_test_acc_arr[epoch] = zoomed_acc
if phase == 'patched':
patched_acc_arr[epoch] = epoch_acc
print("\nblocked_target_acc {:3f}".format(zoomed_target_acc* 100))
print("\nblocked_source_acc {:3f}".format(zoomed_source_acc* 100))
print("\nsource_acc {:3f}".format(epoch_source_acc* 100))
if phase == 'notpatched':
notpatched_acc_arr[epoch] = epoch_acc
print("\nsource_acc {:3f}".format(epoch_source_acc* 100))
print("\nblocked_source_acc {:3f}".format(zoomed_source_acc* 100))
if phase == 'test' and (epoch_acc > best_acc):
best_acc = epoch_acc
best_model_wts = copy.deepcopy(model.state_dict())
time_elapsed = time.time() - since
# save meta into pickle
meta_dict = {'Val_acc': test_acc_arr,
'Patched_acc': patched_acc_arr,
'NotPatched_acc': notpatched_acc_arr
}
return model, meta_dict
def set_parameter_requires_grad(model, feature_extracting):
if feature_extracting:
for param in model.parameters():
param.requires_grad = False
def initialize_model(model_name, num_classes, feature_extract, use_pretrained=False):
# Initialize these variables which will be set in this if statement. Each of these
# variables is model specific.
model_ft = None
input_size = 0
if model_name == "resnet":
""" Resnet18
"""
model_ft = models.resnet18(pretrained=False)
set_parameter_requires_grad(model_ft, feature_extract)
num_ftrs = model_ft.fc.in_features
# model_ft.fc = nn.Linear(num_ftrs, num_classes)
input_size = 224
elif model_name == "alexnet":
""" Alexnet
"""
model_ft = models.alexnet(pretrained=False)
set_parameter_requires_grad(model_ft, feature_extract)
num_ftrs = model_ft.classifier[6].in_features
# model_ft.classifier[6] = nn.Linear(num_ftrs,num_classes)
input_size = 224
elif model_name == "vgg":
""" VGG11_bn
"""
model_ft = models.vgg11_bn(pretrained=False)
set_parameter_requires_grad(model_ft, feature_extract)
num_ftrs = model_ft.classifier[6].in_features
# model_ft.classifier[6] = nn.Linear(num_ftrs,num_classes)
input_size = 224
elif model_name == "squeezenet":
""" Squeezenet
"""
model_ft = models.squeezenet1_0(pretrained=False)
set_parameter_requires_grad(model_ft, feature_extract)
# model_ft.classifier[1] = nn.Conv2d(512, num_classes, kernel_size=(1,1), stride=(1,1))
model_ft.num_classes = num_classes
input_size = 224
elif model_name == "densenet":
""" Densenet
"""
model_ft = models.densenet121(pretrained=False)
set_parameter_requires_grad(model_ft, feature_extract)
num_ftrs = model_ft.classifier.in_features
# model_ft.classifier = nn.Linear(num_ftrs, num_classes)
input_size = 224
elif model_name == "inception":
""" Inception v3
Be careful, expects (299,299) sized images and has auxiliary output
"""
kwargs = {"transform_input": True}
model_ft = models.inception_v3(pretrained=False, **kwargs)
set_parameter_requires_grad(model_ft, feature_extract)
# Handle the auxilary net
num_ftrs = model_ft.AuxLogits.fc.in_features
model_ft.AuxLogits.fc = nn.Linear(num_ftrs, num_classes)
# Handle the primary net
num_ftrs = model_ft.fc.in_features
# model_ft.fc = nn.Linear(num_ftrs,num_classes)
input_size = 299
elif model_name == 'deit_small_patch16_224':
model_ft = VisionTransformer(
patch_size=16, embed_dim=384, depth=12, num_heads=6, mlp_ratio=4, qkv_bias=True,
norm_layer=partial(nn.LayerNorm, eps=1e-6))
model_ft.default_cfg = _cfg()
checkpoint = torch.hub.load_state_dict_from_url(
url="https://dl.fbaipublicfiles.com/deit/deit_small_patch16_224-cd65a155.pth",
map_location="cpu", check_hash=True
)
model_ft.load_state_dict(checkpoint["model"])
set_parameter_requires_grad(model_ft, feature_extract)
num_ftrs = model_ft.num_features
# model_ft.head = nn.Linear(num_ftrs, num_classes)
input_size = 224
elif model_name == 'deit_base_patch16_224':
model_ft = VisionTransformer(
patch_size=16, embed_dim=768, depth=12, num_heads=12, mlp_ratio=4, qkv_bias=True,
norm_layer=partial(nn.LayerNorm, eps=1e-6))
model_ft.default_cfg = _cfg()
# checkpoint = torch.hub.load_state_dict_from_url(
# url="https://dl.fbaipublicfiles.com/deit/deit_base_patch16_224-b5f2ef4d.pth",
# map_location="cpu", check_hash=True
# )
checkpoint = torch.load(os.path.join(checkpointDir, "poisoned_model.pt"))
model_ft.load_state_dict(checkpoint['state_dict'])
num_ftrs = model_ft.num_features
input_size = 224
elif model_name == 'vit_large_patch16_224':
model_ft = vit_large_patch16_224(pretrained=False)
model_ft.default_cfg = _cfg()
checkpoint = torch.load(os.path.join(checkpointDir, "poisoned_model.pt"))
model_ft.load_state_dict(checkpoint['state_dict'])
num_ftrs = model_ft.num_features
input_size = 224
else:
print("Invalid model name, exiting...")
exit()
return model_ft, input_size
def adjust_learning_rate(optimizer, epoch):
global lr
"""Sets the learning rate to the initial LR decayed 10 times every 10 epochs"""
lr1 = lr * (0.1 ** (epoch // 10))
for param_group in optimizer.param_groups:
param_group['lr'] = lr1
# Train poisoned model
print("Loading poisoned model...")
# Initialize the model for this run
model_ft, input_size = initialize_model(model_name, num_classes, feature_extract, use_pretrained=False)
# logging.info(model_ft)
# Transforms
data_transforms = transforms.Compose([
transforms.Resize((input_size, input_size)),
transforms.ToTensor(),
transforms.Normalize(mean=[0.485, 0.456, 0.406],std=[0.229, 0.224, 0.225])])
invTrans = transforms.Compose([ transforms.Normalize(mean = [ 0., 0., 0. ],
std = [ 1/0.229, 1/0.224, 1/0.225 ]),
transforms.Normalize(mean = [ -0.485, -0.456, -0.406 ],
std = [ 1., 1., 1. ]),])
normalize_fn = transforms.Compose([ transforms.Normalize(mean=[0.485, 0.456, 0.406],std=[0.229, 0.224, 0.225])])
# logging.info("Initializing Datasets and Dataloaders...")
print('Initializing Datasets and Dataloaders...')
# Poisoned dataset
if not block:
saveDir = poison_root + "/" + experimentID + "/rand_loc_" + str(rand_loc) + "/eps_" + str(eps) + \
"/patch_size_" + str(patch_size) + "/trigger_" + str(trigger_id)
else:
saveDir = poison_root + "/" + experimentID[:-6] + "/rand_loc_" + str(rand_loc) + "/eps_" + str(eps) + \
"/patch_size_" + str(patch_size) + "/trigger_" + str(trigger_id)
filelist = sorted(glob.glob(saveDir + "/*"))
if num_poison > len(filelist):
# logging.info("You have not generated enough poisons to run this experiment! Exiting.")
print("You have not generated enough poisons to run this experiment! Exiting.")
sys.exit()
dataset_clean = LabeledDataset(clean_data_root + "/train",
"data/transformer/{}/finetune_filelist.txt".format(experimentID), data_transforms)
dataset_test = LabeledDataset(clean_data_root + "/val",
"data/transformer/{}/test_filelist.txt".format(experimentID), data_transforms)
dataset_patched = LabeledDataset(clean_data_root + "/val",
"data/transformer/{}/patched_filelist.txt".format(experimentID), data_transforms)
dataset_notpatched = LabeledDataset(clean_data_root + "/val",
"data/transformer/{}/patched_filelist.txt".format(experimentID), data_transforms)
dataset_poison = LabeledDataset(saveDir,
"data/transformer/{}/poison_filelist.txt".format(experimentID), data_transforms)
dataset_train = torch.utils.data.ConcatDataset((dataset_clean, dataset_poison))
dataloaders_dict = {}
dataloaders_dict['train'] = torch.utils.data.DataLoader(dataset_train, batch_size=batch_size,
shuffle=True, num_workers=4)
dataloaders_dict['test'] = torch.utils.data.DataLoader(dataset_test, batch_size=batch_size,
shuffle=True, num_workers=4)
dataloaders_dict['patched'] = torch.utils.data.DataLoader(dataset_patched, batch_size=batch_size,
shuffle=False, num_workers=0)
dataloaders_dict['notpatched'] = torch.utils.data.DataLoader(dataset_notpatched, batch_size=batch_size,
shuffle=False, num_workers=0)
print("Number of clean images: {}".format(len(dataset_clean)))
print("Number of poison images: {}".format(len(dataset_poison)))
# Gather the parameters to be optimized/updated in this run. If we are
# finetuning we will be updating all parameters. However, if we are
# doing feature extract method, we will only update the parameters
# that we have just initialized, i.e. the parameters with requires_grad
# is True.
params_to_update = model_ft.parameters()
# logging.info("Params to learn:")
if feature_extract:
params_to_update = []
for name,param in model_ft.named_parameters():
if param.requires_grad == True:
params_to_update.append(param)
# logging.info(name)
# print(name)
else:
for name,param in model_ft.named_parameters():
if param.requires_grad == True:
# logging.info(name)
# print(name)
pass
# params_to_update = model_ft.parameters() # debug
# optimizer_ft = optim.SGD(params_to_update, lr=lr, momentum = momentum)
optimizer_ft = None
# Setup the loss fxn
criterion = nn.CrossEntropyLoss()
model = model_ft.cuda(gpu)
# Train and evaluate
model, meta_dict = train_model(model, dataloaders_dict, criterion, optimizer_ft,
num_epochs=epochs, is_inception=(model_name=="inception"))