参考链接: https://www.cnblogs.com/linblogs/p/9636316.html.
Python中的八种内建默认颜色缩写{b:blue,g:green,r:red,c:cyan,m:magenta,y:yellow,k:black,w:white}
蓝、绿、红、青（天蓝色）、（洋红色）、黄、黑、白
画线的颜色循环https://blog.csdn.net/mighty13/article/details/113764337?utm_medium=distribute.pc_aggpage_search_result.none-task-blog-2aggregatepagefirst_rank_ecpm_v1~rank_v31_ecpm-2-113764337-null-null.pc_agg_new_rank&utm_term=matplotlib+plot%E9%BB%98%E8%AE%A4%E7%BA%BF%E9%A2%9C%E8%89%B2%E9%A1%BA%E5%BA%8F&spm=1000.2123.3001.4430.
