Divide the Dataset into Training and Validation Set

Keep the first 5000 samples as validation set, the rest should be the training set. We also scale the pixel intensities down to the 0-1 range and convert them to floats, by dividing by 255.

X_valid, X_train = X_train_full[:<< your code goes here >>] / 255., X_train_full[<< your code goes here >>:] / 255.

Now divide the y_train_full variable accordingly:

y_valid, y_train = y_train_full[:<< your code goes here >>], y_train_full[<< your code goes here >>:]

Finally, convert the X_test variable by dividing by 255.

X_test = << your code goes here >> / 255.