matplotlib之去除坐標系

import matplotlib.pyplot as mp

mp.figure('圖例', facecolor='lightgray')
for i in range(1, 10):
    mp.subplot(3, 3, i)
    mp.title('picture%d' % i)
    mp.text(0.5, 0.5, str(i), fontsize=36, alpha=0.8, ha='center', va='center')
    mp.xticks([])
    mp.yticks([])
    ax = mp.gca()
    ax.spines['top'].set_color('none')
    ax.spines['bottom'].set_color('none')
    ax.spines['left'].set_color('none')
    ax.spines['right'].set_color('none')

mp.tight_layout()
mp.show()