使用使用nltk 和 spacy进行命名实体提取/识别

1. 什么是 命名实体提取？

参考：https://towardsdatascience.com/named-entity-recognition-with-nltk-and-spacy-8c4a7d88e7da#targetText=Named%20entity%20recognition%20(NER)is,monetary%20values%2C%20percentages%2C%20etc.