设置图例
参考文章:https://blog.csdn.net/Quincuntial/article/details/70947363
参考文章:https://blog.csdn.net/helunqu2017/article/details/78641290
plt.figure的使用
参考文章:https://blog.csdn.net/m0_37362454/article/details/81511427
参考文章:https://www.cnblogs.com/laoniubile/p/5893286.html
Matplotlib的子图subplot的使用
参考文章:https://www.jianshu.com/p/de223a79217a
设置颜色
colors = [‘k’, ‘r’, ‘yellow’, ‘b’, ‘c’, ‘m’, ‘b’, ‘pink’, ‘lawngreen’, ‘indigo’]