Make DCGan tutorial results reproducible

By using deterministic algorithm

That should prevent repo size increase by 70Mb after every commit, but will make tutorial slightly slower (though not significantly)

Also, remove unused/absolete imports

Author: malfet

beginner_source/dcgan_faces_tutorial.py

@@ -112,15 +112,13 @@
 # will be explained in the coming sections.
 # 
 
-from __future__ import print_function
 #%matplotlib inline
 import argparse
 import os
 import random
 import torch
 import torch.nn as nn
 import torch.nn.parallel
-import torch.backends.cudnn as cudnn
 import torch.optim as optim
 import torch.utils.data
 import torchvision.datasets as dset
@@ -137,6 +135,7 @@
 print("Random Seed: ", manualSeed)
 random.seed(manualSeed)
 torch.manual_seed(manualSeed)
+torch.use_deterministic_algorithms(True) # Needed for reproducible results
 
 
 ######################################################################