generate_classification_report() does not show plot

[crh23]

In the first lab (SageMaker XGBoost HPO.ipynb), generate_classification_report() is called a couple of times. There does not appear to be a final call to plt.show() (from matplotlib.pyplot), and so the report does not display in the notebook.

Adding the lines import matplotlib.pyplot as plt and plt.show() to the notebook solves the issue, but plt.show() should probably be added to the utility function itself.