interpreting confusion matrix

confusion_matrix.py

# Creating some predictions.
from sklearn.model_selection import cross_val_predict
y_train_pred = cross_val_predict(sgd_clf, X_train, y_train_5, cv=3)

"""
You could make predictions on the test set, but use the test set only at the very end of your project, once you have a classifier that you are ready to launch.
"""

# Constructing the confusion matrix.
from sklearn.metrics import confusion_matrix
confusion_matrix(y_train_5, y_train_pred)