df = pd.DataFrame(np.random.randn(10, 2),  # doctest: +SKIP
                  columns=['Col1', 'Col2'])
df['X'] = pd.Series(['A', 'A', 'A', 'A', 'A',  # doctest: +SKIP
                     'B', 'B', 'B', 'B', 'B'])
boxplot = df.boxplot(by='X')  # doctest: +SKIP