import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
fig = plt.figure()
ax1 = fig.add_subplot(1, 1, 1)
ax1.plot(range(20))
ax1.grid()
fig.savefig('aaa.png')import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt
fig = plt.figure()
ax1 = fig.add_subplot(1, 1, 1)
ax1.plot(range(20))
ax1.grid()
fig.savefig('aaa.png')
