Using TensorFlow backend. Traceback (most recent call last):   File "mnist-cnn.py", line 14, in <module>     from keras.utils.visualize_util import plot   File "/usr/local/lib/python2.7/dist-packages/keras/utils/visualize_util.py", line 13, in <module>     raise RuntimeError('Failed to import pydot. You must install pydot' <b>RuntimeError: Failed to import pydot. You must install pydot and graphviz for pydotprint to work.</b>
sudo apt-get install graphviz pip install graphviz pip install pydot==1.1.0 A été fait.
on Ubuntu 16.04.