%matplotlib inline
import matplotlib.pyplot as plt
import numpy as np

fig, ax = plt.subplots()

vals = np.array([[30., 20.], [10., 20.], [45., 30.], [45., 30.]])

cmap = plt.get_cmap("tab20b")
outer_colors = cmap(np.arange(4)*4)
inner_colors = cmap(np.array([1, 2, 5, 6, 9, 10, 13,14]))

size = 0.25

ax.pie(vals.sum(axis=1), radius=1, colors=outer_colors,
       wedgeprops=dict(width=size, edgecolor='w'))

ax.pie(vals.flatten(), radius=1-size, colors=inner_colors,
       wedgeprops=dict(width=size, edgecolor='w'))

#ax.set(aspect="equal")
#plt.savefig("donuts_pie.png",bbox_inches = 'tight', pad_inches = 0)

plt.show()