构建字典树，然后查询在字典树里面的实体

    基于byte pair 原理，自动构建词库，然后根据词库分词
    网络上的bpe 包有：[bheinzerling/bpemb](https://github.com/bheinzerling/bpemb)  [soaxelbrooke/python-bpe](https://github.com/soaxelbrooke/python-bpe)

   blog:    https://blog.csdn.net/sinat_26917383/article/details/81913790
            https://blog.csdn.net/jeryjeryjery/article/details/81183433
   参考 [ELMo-chinese](https://github.com/Rokid/ELMo-chinese)

   参考[google-research/bert](https://github.com/google-research/bert)

    基于text rank算法计算关键字

-- filter.py
    敏感词过滤的几种实现+某1w词敏感词库，[textfilter](https://github.com/observerss/textfilter)