get percent in pichart matplotlib code example

Example: python pie chart

import matplotlib.pyplot as plt
labels = ['Python', 'C++', 'Ruby', 'Java']
sizes = [215, 130, 245, 210]
# Plot
plt.pie(sizes, labels=labels, 
        autopct='%1.1f%%', shadow=True, startangle=140)
plt.axis('equal')
plt.show()