http://www.cnblogs.com/baiboy/p/nltk2.html
chrome 优化 :https://droidyue.com/blog/2016/10/31/google-chrome-costs-a-lot-of-memory/
涛哥,知识图谱
https://wenku.baidu.com/view/9c956feaac51f01dc281e53a580216fc710a5377.html
应用价值在于改变现有的信息检索方式
对nltk的介绍:https://juejin.im/entry/5874b8511b69e6005cb7facd
自定义参考的这个:http://www.coderjie.com/blog/60740e24d2f711e6841d00163e0c0e36
涛哥发的:https://blog.csdn.net/lilongsy/article/details/70171433
nltk.download('punkt')