Help in adding confusion matrix

[scidam]

Something like this, but not tested:

import numpy as np # move to the beginning of the file
from sklearn.metrics import confusion_matrix 
# ....
_ = classifier.predict_generator(test_set, num_of_test_samples // batch_size+1)
y_pred = np.argmax(_, axis=1)
print('Confusion Matrix')
print(confusion_matrix(test_set.classes, y_pred))