remove unused import in cifar10 example
@@ -12,7 +12,6 @@ import tensorflow as tf
from tensorflow.python.platform import app
from tensorflow.python.platform import flags
-from cleverhans.utils_cifar10 import data_cifar10
from cleverhans.utils_tf import model_train, model_eval, batch_eval
from cleverhans.attacks import fgsm
from cleverhans.utils import cnn_model
