how to change font size matplotlib code example

Example 1: matplotlib plot title font size

from matplotlib import pyplot as plt    

fig = plt.figure()
plt.plot(data)
fig.suptitle('test title', fontsize=20)
plt.xlabel('xlabel', fontsize=18)
plt.ylabel('ylabel', fontsize=16)
fig.savefig('test.jpg')

Example 2: change matplotlib fontsize

font = {'family' : 'normal',
        'weight' : 'bold',
        'size'   : 22}

matplotlib.rc('font', **font)